# Poster Abstracts

## X-class flares released during the peak of the decline phase of SC24, a descriptive study

Eruptive X-class flares occurring during the peak and decline phases of the solar cycle 24 are stronger than those of the solar cycle 23. We notice that the solar cycle 24 is the weakest in the last 100 years. The last two cycles are very weak compared to other cycles, except for the Dalton Minimum cycles 4, 5, 6 and 7; which indicates the appearance of a new Dalton minimum during 23, 24, 25 and 26. During the last 5 solar cycles, a new peak has appeared releasing high energetic particles and X-class solar flares which are called the secondary peak or the double peak of the solar cycle.The aim of this descriptive study is to follow the X-class flares released during the peak and decline phase of SC24, once they are released, to compare it with other solar cycles.The causes of the release of such eruptive storms, through the year 2014, during the double peak of the solar cycle 24 are also discussed.

## A coordinate-independent characterization of a black hole shadow

We provide a general formalism to describe the shadow as an arbitrary polar curve expressed in terms of a Legendre expansion. Our formalism does not presume any knowledge of the properties of the shadow, e.g. the location of its centre, and offers a number of routes to characterize the distortions of the curve with respect to reference circles. These distortions can be implemented in a coordinate-independent manner by different teams analysing the same data. We show that the new formalism provides an accurate and robust description of noisy observational data, with smaller error variances when compared to previous approaches for the measurement of the distortion.

## Optical properties of a braneworld black hole

We study optical properties in terms of weak and strong (retrolensing) gravitational lensing around a black hole on the brane. The black hole is described by the Reissener-Nordström metric, where the electric charge is replaced by the Weyl tidal charge which acts in consonance with mass. It is, therefore, expected that gravitational lensing effects would be enhanced by the tidal charge, and that is what we verify. We also study the shadow of a braneworld black hole in plasma and show that the tidal charge increases the size of the black hole shadow. We finally consider energy emission from the hole by thermal radiation which is also increased due to tidal charge.

## Magnetic fields of spherical compact stars in modified theories of gravity

The stellar magnetic field configuration and solutions of Maxwell equations in the external background spacetime of a magnetized spherical stars in the Horava-Lifshitz gravity and in modified f(R) gravity are studied. The star is modeled as a sphere consisting of perfect highly magnetized fluid with infinite conductivity and frozen-in magnetic field. With respect to solutions for magnetic fields found in the Schwarzschild spacetime star in modified gravity theories, enhancing corrections are added to the exterior magnetic field. The energy losses through magnetodipolar radiation of the rotating magnetized compact star within alternative gravity theories is also considered. The question of whether these models can be considered as an alternative theory for general relativity is also discussed through astrophysical application of the obtained magnetodipolar energy loss formula. Finally we analyze the role of general relativistic effect on the decay of a neutron star’s magnetic field in modified theories of gravity.

## An UXor among FUors: Extinction-related Brightness Variations of the Young Eruptive Star V582 Aur

Abraham, Peter

V582 Aur is an FU Ori-type young eruptive star in outburst since ~1985. The eruption is currently in a relatively constant plateau phase, with photometric and spectroscopic variability superimposed. Here we will characterize the progenitor of the outbursting object, explore its environment, and analyze the temporal evolution of the eruption. We are particularly interested in the physical origin of the two deep photometric dips, one that occurred in 2012 and one that is ongoing since 2016. We collected archival photographic plates and carried out new optical, infrared, and millimeter-wave photometric and spectroscopic observations between 2010 and 2018, with a high sampling rate during the current minimum. Besides analyzing the color changes during fading, we compiled multiepoch spectral energy distributions and fitted them with a simple accretion disk model. Based on pre-outburst data and a millimeter continuum measurement, we suggest that the progenitor of the V582 Aur outburst is a low-mass T Tauri star with average properties. The mass of an unresolved circumstellar structure, probably a disk, is 0.04 M ?. The optical and near-infrared spectra demonstrate the presence of hydrogen and metallic lines, show the CO band head in absorption, and exhibit a variable Ha profile. The color variations strongly indicate that both the ~1 yr long brightness dip in 2012 and the current minimum since 2016 are caused by increased extinction along the line of sight. According to our accretion disk models, the reddening changed from A V = 4.5 to 12.5 mag, while the accretion rate remained practically constant. Similarly to the models of the UXor phenomenon of intermediate- and low-mass young stars, orbiting disk structures could be responsible for the eclipses.

Abrahamyan, Hayk

## Galaxy evolution in groups observed by the Integral Field Spectrograph MUSE, a dynamical approach

Abril Melgarejo, Valentina

Galaxies are strongly affected by their environment, various mechanisms seem to occur in dense environments to remove gas efficiently from galaxies. In particular, Star forming quenching and the build up of the red sequence happen earlier in dense environments than in field (e.g. Peng et al. 2010). The goal of this project is then to understand the impact of the environment on galaxy mass assembly mechanisms and on the establishment of the Hubble sequence observed in the local Universe. The influence of the environment seems to begin to be effective between z = 0 and z = 1, when cosmic star formation begins to decrease.Studying spatially resolved and integrated properties of star forming galaxies at z<1, may help in better understanding the various processes responsible for the transition. However, up to now all this kind of studies have been performed independently from the environmental effects and in the high galaxy mass regime due to the sample structures and/or observational limitations. This project is based on the exploitation of a unique sample from GTO MUSE VLT observations targeted on groups between 0.3 <z <1,="" complemented="" for="" all="" the="" groups="" with="" hst="" images.="" current="" morpho-kinematic="" analysis="" has="" been="" performed="" on="" sample="" consisting="" so="" far="" in="" ~="" 330="" galaxies="" inside="" at="" different="" redshifts.="" we="" make="" special="" emphasis="" a="" sub-sample="" of="" 100="" z="" 0.7="" which="" obtained="" preliminary="" results="" their="" tully-fisher="" relationship.the="" spatially="" resolved="" kinematics,="" can="" better="" constrain="" processes="" galaxy="" mass="" assembly="" and="" provides="" clues="" how="" baryons="" are="" accreted="" dark="" matter="" halos.="" comparison="" similar="" studies="" low="" density="" environments="" will="" ultimately="" allow="" to="" probe="" impact="" environment="" evolution="" mechanisms="" galaxies.<="" p="">
</z></z></z></z></z></z>

## NOC Activity in Nepal

Acharya, Jayanta

Nepal is least develop country lies in between two big country India and China. Despite the favorable climatic and geographical conditions, research and development of the astronomy in Nepal is very limited.To increase the astronomical awareness there should be activities in School and Public Places. Our  activities aware not only to children but also to the school teachers parents and locals people in a practical way. If a children is interested in astronomy he/she continue their study in astronomy. They conduct research and development in this field.In this poaster we are showing how are are doing Astronomical activities and increasing interest for the students for the future astronomer.Key words: Astronomy, School,

## Astronomy Education and outreach for Earthquake affected Nepali students.

Acharya, Jayanta

Nepali Culture has many strong believe in communicating the Astronomy. There are some superstition. People think anything happen uncertain they blame some heavenly planets stars or Moon. Still people think earthquake is just because of the planets positions. Many reputed News paper journalists goes to the local priests to ask about future earthquake and any other changes. We organized a Astronomy Activities for the Earthquake affected students in three different places Gorkha, Nuwakot and Kathmandu most earthquake affected district in Nepal. there was 8.2 magnitude earthquake in 2015, and Hundreds of thousands of people their school going children were made homeless with entire villages flattened, across many districts of the country by the earthquake. Centuries-old buildings including many schools were destroyed. We thought Astronomy may help them to forget the fear of the earthquake because of it will be unique and new for their school activities. We are focused our activities in the one, school which are most affected in Nepal. In my talk I would like to explain and how we did Authentic and scientifically explained about earthquake through Astronomy education and outreach.Keywords: Astronomy, Earthquake, Telescope.

## Determining effects of telescope spatial resolution with synthetic observations of galaxy simulations

Acharyya, Ayan

How well can we recover metallicity gradient in galaxies, given telescope limitations? We produce realistic synthetic IFU data cubes from Enzo simulations of star forming disk galaxies, by including the effects of telescope resolution and instrumental noise, to understand the observation of metallicity gradients. We conduct a parameter study to specifically investigate the effect of spatial resolution and signal-to-noise ratio (SNR) on inferred metallicity gradient. I will present our new MAPPINGS photoionization models of HII regions and the steps involved to produce the mock data cubes. I will also discuss the results and their implications on the metallicity gradient measurements currently being carried out as part of large IFU surveys like SAMI. We find that, at a given spatial resolution the accuracy of the inferred gradient saturates to a “best possible” value, irrespective of how high the SNR is. The magnitude of this accuracy depends on the true gradient and the metallicity diagnostic used. I will also discuss the effects of imposing a SNR threshold criteria. In future, we plan to use other hydrodynamical simulations with different underlying physics, to generate our mock observations. Comparing the different mock observations with real IFU observations will help us constrain the physical processes in the observed galaxies.

## Multiplicity Among Young Stellar Objects in Orion A

Ackerl, Christine

The initial multiplicity properties of stars carry the footprints of the mechanisms involved in their formation. Additionally, multiplicity also plays an important role in planet formation or even habitability. It is therefore inevitable to study under which circumstances stars form alone or in multiples and how their separations evolve over time. While multiplicity among main sequence stars is already well established (e.g. Duquennoy & Mayor 1991) this is not the case for young stellar objects. Studies concentrating on young binaries are mostly carried out for relatively small populations and in very distinct environments, for that reason, the results are ambivalent and leave unanswered questions. For example, whether and how does initial stellar multiplicity depend on environmental conditions? In order to provide a more complete picture, a statistically significant sample of young binaries that covers an entire star forming region with diverse physical conditions is needed. Using the Vienna Survey in Orion (Meingast et al. 2016) we are able to present the largest known sample of young visual binaries towards one single star forming cloud, the rich and nearby star forming region Orion A. The survey provides high-quality seeing limited ESO-VISTA images and JHKs-photometry for ~800,000 sources and covers a vast range of different star forming environments, from well known dense clusters to isolated (Taurus-like) environments towards the southern end of Orion A. Our sample is sensitive to separations > 300 AU and is about an order of magnitude larger when compared to previous studies in this region (e.g. Kounkel et al. 2016).

## Space Mission Geometry for Almost Every Purpose

Acton, Charles

Every space mission needs some form of space geometry–positions, velocities, orientations and more–from the very earliest design stages through the analysis of science or other results that may extend to many years after the end of operations.   These kinds of space geometry computations can be rather difficult to make given that everything is moving or rotating; given that a number of reference frames and coordinate systems come into play; given that estimates of size, shape and orientation of target bodies are frequently revised; and given that several time systems are used.      Realizing the challenges and also the importance of making accurate space geometry computations, NASA established an organization–the Navigation and Ancillary Information Facility (NAIF) to implement a multi-mission, enduring process, named SPICE1, for computing space mission geometry.   SPICE comprises both ancillary data files, called “kernels,” and a suite of software used to produce those kernels and to compute derived quantities such as altitude, latitude/longitude, lighting angles, etc. from the data contained within the kernels. The SPICE software is available in six languages, and for most popular computing environments. The software is extensively documented and throughly tested; tutorials and training classes on its use are offered. NASA offers SPICE free of charges, export restrictions and licensing arrangements: literally anyone, worldwide, can obtain and use the SPICE components.   This presentation will provide examples of where and how SPICE has and is being used and it will look to the future of SPICE–what new capabilities are being added and where it might be helpful in new solar system engineering and science activities.1Spacecraft, Planet, Instrument, Camera-matrix, Events

## A 3.5-million Solar Masses Black Hole in the Centre of the Ultracompact Dwarf Galaxy Fornax UCD3

Afanasiev, Anton

The origin of ultracompact dwarfs (UCDs), a class of compact stellar systems discovered two decades ago, still remains a matter of debate. Recent discoveries of central supermassive black holes in UCDs likely inherited from their massive progenitor galaxies provide support for the tidal stripping hypothesis. At the same time, on statistical grounds, some massive UCDs might be representatives of the high luminosity tail of the globular cluster luminosity function. Here we present a detection of a 3.5±1.4 × 106 MSun black hole (1s uncertainty) in the centre of the UCD3 galaxy in the Fornax cluster, that corresponds to 4% of its stellar mass. From Jeans dynamical modelling of the UCD3 internal kinematics obtained with the SINFONI spectrograph at the ESO Very Large Telescope using adaptive optics, we rule out the zero black hole mass at the 3s confidence level. This is the fourth supermassive black hole found in a UCD and the first one in the Fornax cluster. Similarly to other known UCDs that harbour black holes, UCD3 hosts metal rich stars enhanced in a-elements that supports the tidal stripping of a massive progenitor galaxy as its likely formation scenario. We estimate that up to 80% of luminous UCDs in galaxy clusters host central black holes. This fraction should be lower for UCDs in groups, because their progenitors are more likely to be dwarf galaxies, which do not tend to host very massive black holes upon formation.

## Visualisation: where data meets insight

Afonso, Ana

One of the most regular activities that we are required to do in Astronomy is to present our data to others (such as papers, talks, etc). However, how well are our plots  highlighting the results? I would like to demonstrate some examples of how to (and how not to) show astronomical data results and share some of tips and tricks to produce high quality and efficient ways to make data understandable to everyone.

## Galaxy clusters mergers, shocks and turbulence: what are the effects on galaxy evolution?

Afonso, Ana

Galaxy populations in relaxed clusters are dominated by ellipticals. However, little is known about the effect of disturbed clusters on galaxy evolution. Merging clusters represent an extremely violent environment permeated by Mpc-wide shock waves and cluster-wide turbulence. Stroe et al. (2016) completed the first narrow-band survey of Ha emitters in a sample of low-redshift clusters sampling a range of masses and relaxation states. The results have shown that relaxed environments have 25 times fewer Ha emitters when compared to merging clusters. What drives this reversal of typical environmental trends and how could shocks and turbulence trigger star formation in cluster galaxies remains unclear. Multi-object spectroscopic observations have been obtained using VLT/VIMOS and WHT/AF2 in order to efficiently follow-up star-forming galaxies and AGNs uniformly selected in relaxed and merging clusters. This allowed us to measure the precise redshift, powering source, metallicity, electron density and ionization parameters of these sources as well as to correlate the optical spectroscopic properties with the galaxy morphologies. Given the similarities between low-redshift disturbed clusters and high-redshift protoclusters, this unique study not only provides an excellent opportunity to connect observations and theory but it may also provide important clues to the evolution of galaxies at high-redshift analogs.

## On the UV compactness and morphologies of typical Lya emitters from z~ 2 to z~ 6

Afonso, Ana

Lya is, intrinsically, the strongest nebular emission line in actively star-forming galaxies (SFGs), but its resonant nature and uncertain escape fraction limit its applicability. The structure, size, and morphology may be key to understand the escape of Lya photons and the nature of Lya emitters (LAEs). In Paulino-Afonso et al. (2018) we investigate the rest-frame UV morphologies of a large sample of ~4000 LAEs from z~2 to z~6, selected in a uniform way with 16 different narrow- and medium-bands over the full COSMOS field (SC4K, Sobral et al., 2018). From the magnitudes that we measure from UV stacks, we find that these galaxies are populating the faint end of the UV luminosity function. We find also that LAEs have roughly the same morphology. The median size, ellipticities, Sérsic index, and light concentration show little to no evolution. LAEs with the highest equivalent widths are the smallest/most compact. In a scenario where galaxies with a high Lya escape fraction are more frequent in compact objects, these results are a natural consequence of the small sizes of LAEs. When compared to other SFGs, LAEs are found to be smaller at all redshifts. The difference between the two populations changing with redshift, from a factor of ~1 at z=5 to SFGs being a factor of ~2-4 larger than LAEs for z=2. This means that at the highest redshifts, where typical sizes approach those of LAEs, the fraction of galaxies showing Lya in emission should be much higher, consistent with observations. In this era of new and upcoming cutting-edge facilities, linking the theoretical perspectives and numerical simulations with the observational studies of the properties of the LAEs across the Universe seems to be a key to understand reionization and early stages of galaxy formation.

## Understanding the cold circumgalactic medium around galaxies

Afruni, Andrea

The circumgalactic medium (CGM) of galaxies consists of a multiphase gas with components at very different temperatures, from 10^4 to 10^7 K. It constitutes the interface between the interstellar medium and the intergalactic medium (IGM) and modelling its kinematics and dynamics is critical for our understanding of the role of feedback and gas accretion in galaxy evolution. Moreover, the large amount of mass of this gas suggests that it can contain a significant part of the galaxy ‘missing baryons’. The most puzzling component of this medium is the low-temperature (T~10^4 K) material detected via UV-optical absorptions towards background QSOs. The ubiquitous presence of this material has recently been established both around star-forming and early-type galaxies, but the origin, dynamics and fate of this medium are still unclear. We have modelled this cold gas as an inflow of clouds from the IGM to the central galaxies and compared our model predictions with the observations of the COS-Halos collaboration. We found that in massive early-type galaxies the observed kinematics is only reproduced if the cold CGM clouds are destroyed by the hydrodynamical interactions with the hot gas and do not reach the central galaxies, explaining in this way the quenching of these passive galaxies. On the contrary, in low-mass star-forming galaxies the models successfully reproduce the kinematics with cold CGM clouds reaching the inner regions and accreting onto the central galaxies. This scenario suggests that the fate of the cold CGM has a crucial role in the evolution of star formation in galaxies. Moreover, through the comparison with the observations, our models allow us to give an estimate of the mass of the cold CGM gas in galaxies, resulting to be a significant part of the total galaxy baryonic mass.

## X-ray reprocessing: Through the eclipse spectra of high and low mass X-ray binaries with XMM-NEWTON

Aftab, Nafisa

Study of X-ray reprocessing is one of the key diagnostic tool to probe the environment in X-ray binary systems. Difficult aspect to study X-ray reprocessing is the presence of primary radiation from the compact star along with the reprocessed radiation. Eclipsing X-ray binaries make an ideal condition to study reprocessed X-rays, as the X-rays detected during eclipse are purely reprocessed while the primary X-rays are blocked by the companion star. We carried out first comprehensive studies of X-ray reprocessing with a number of eclipsing High Mass X­-ray Binary and Low Mass X­-ray Binary (HMXB and LMXB) systems during and outside eclipse with XMM­-NEWTON EPIC pn. Comparing eclipse and out-of-eclipse spectra of these sources we have found ample diversity in the X-ray reprocessing characteristics in HMXBs, even in the same source at different epochs the variation is quite large. In spite of having much weaker wind environment, the flux ratio of out-of-eclipse to eclipse in LMXBs is in a range comparable to the HMXBs. The analysis shows very strong Iron ka emission line during eclipse phases in most of the HMXBs and week or no Iron emission lines in LMXBs. Equivalent width of Iron emission lines in Supergiant Fast X-ray Transients (SFXTs) are large during eclipse, similar to that in Supergiant HMXBs (SgHMXBs). There are some significant system to system differences. For example low equivalent width of Iron ka emission line in HMXB Cen X-3 during eclipse, very week Iron emission line in HMXB SMC X-1,  comparable out-of-eclipse to eclipse flux ratio in LMXB  AXJ 1745.6–2901 irrespective of intensity state etc. Overall we try to infer the wind and accretion disk characteristics, which are the reprocessing agents in the HMXB and LMXB systems respectively.

## On the basins of convergence of the libration point in the axisymmetric restricted five-body problem: Convex case

Aggarwal, Rajiv

In the resent paper, we have numerically explored the fractal basins of convergence associated with the libration points in the axisymmetric restricted problem of five-bodies. The four bodies are supposed to be in axisymmetric central configurations as discussed by Érdi and Czirják (2016) and the dynamics of the fifth body moving under the gravitational influence of them are analyzed. We have considered the convex case which is one of the cases of the three basic axisymmetric central configurations proposed by Érdi and Czirják. This can be visualized by taking a system of three masses on a straight line and then dividing one of the masses into two equal halves to put them up and down in such a manner that the resulting four point masses configuration is symmetric about the x-axis. The convex case is taken into consideration which can be obtained by splitting the central mass to form a four-sided polygon. We have also unveiled numerically the domain of convergence corresponding to libration points by using the multivariate version of the Newton-Raphson iterative scheme. The correlations between the basins of convergence associated with libration points and the required number of iterations corresponding to it are also presented and discussed in detail. The present numerical analysis reveal that the evolution of the attracting domains in this dynamical system is enormously complicated but worth studying issue._x005F References:_x005F Érdi, B., Czirják, Z.: Central configurations of four bodies with an axis of symmetry. Celest. Mech. Dyn. Astron. 125(1), 33–70 (2016) _x005F Gao, C., Yuan, J., Sun, C.: Equilibrium points and zero velocity surfaces in the axisymmetric restricted five-body problem. Astrophys Space Sci. 362:72 (2017)

## Large-scale distribution of hot gas from Sunyaev-Zeldovich

Aghanim, Nabila

The distribution of ionised hot gas in the cosmic structure was recently unveiled through measurement of the Sunyaev-Zeldovich (SZ) effect by Planck satellite over the whole sky. I will review the main results showing how SZ effect probes the multi-scale distribution of hot gas from halos to the largest structure in the Universe.

## Variability of magnetically-dominated jets in blazars and gamma ray bursts

Agnieszka, Janiuk

The fastly variable accretion flows are found in a number of different types of astrophysical black hole sources. At largest scales, they are present in the cores of active galaxies.In the radio-loud objects, such as blazars, the variability of the inflow can be transmitted to the outflow properties. In these sources,the relativistic jets are pointing to our line of sight.In addition, many similarities are found between the jet physics in blazars and in gamma ray bursts.The latter are observed from extragalactic distances, butoperate at smaller scales, within the stellar-mass accreting black holes and in collapsing star's environment.Observational studies have shown an anticorrelation between minimum variability time scale and Lorentz factor of the emitted jet.Motivated by those observational properties of black hole sources, we investigate the accretion inflow and outflow properties,by means of numerical GRMHD simulations.Our two-dimensional magneto-hydrodynamical models are computed in full General Relativity, implemented with the code HARM. The properties ofmagnetic fields and their role in evolution in the flows are studied in detail.The blazar jet is Poynting-dominated, and powered by the Blandford-Znajek mechanism which can extract energy from a rotating black hole. This mechanism is nowwell known and tested in the purpose of a jet launching, but observations are showing variability in the jet emission. Multiple shocks that collide in the jet,can lead to multiple emission episodes and can account for the fluctuating light curve. A reasonable interpretation of this effect is that the variabilityobserved in the jets can directly reflect the central engine variability. The latter is tightly related to the action of magnetic fields in the center of thegalaxy.

## Relativistic Astrophysics in Uzbekistan

Ahmedov, Bobomurat

It is necessary to underline that during the last twenty years due to the help and assistance of the international scientific community  there was a great success in the development and establishment of new well functioning and competitive scientific groups specialized in general relativity and relativistic astrophysics in Uzbekistan (Tashkent), Kazakhstan (Astana and Almaty), Kyrgyzstan (Bishkek). The great achievements are made in Uzbekistan (the most populated  Central Asian republic), and together with our European and South Asian collaborators, we have obtained interesting results on Relativistic Astrophysics of Compact Gravitational Objects published in more than one hundred papers in the refereed journals with the involvement of European, Central and South Asian scientists.

## SCALAR AND ELECTROMAGNETIC PERTURBATIONS OF NONSINGULAR NONROTATING BLACK HOLES IN CONFORMAL GRAVITY

Ahmedov, Bobomurat

We study scalar and electromagnetic perturbations of a family of nonsingular nonrotating blackhole spacetimes that are solutions in a large class of conformally invariant theories of gravity.The effective potential for scalar perturbations depends on the exact form of the scaling factor.Electromagnetic perturbations do not feel the scaling factor, and the corresponding quasinor- malmode spectrum is the same as in the Schwarzschild metric. We find that these black hole metrics arestable under scalar and electromagnetic perturbations. Assuming that the quasi- normal modespectrum for scalar perturbations is not too different from that for gravitational perturbations,we can expect that the calculation of the quasinormal mode spectrum and the observation withgravitational wave detectors of quasinormal modes from astrophysical blackholes can constrain the scaling factor and test these solutions.

## PLASMA MAGNETOSPHERE OF OSCILLATING AND ROTATING MAGNETIZED NEUTRON STARS

Ahmedov, Bobomurat

We discuss a number of analytical studies, aimed at adding the influence of oscillations experienced by a pulsar/magnetar on its plasma magnetopshere. We show that particular modes ofoscillations may considerably increase the pulsar/magnetar luminosity and apply the obtainedtheoretical results on the plasma magnetosphere of oscillating and rotating neutron stars i) topropose a qualitative model for the explanation of the phenomenology of intermittent part timepulsars, ii) to study the conditions for radio emission in rotating and oscillating magnetars byfocusing on the main physical processes determining the position of their death lines, i.e. ofthose lines that separate the regions where the neutron star may be radio loud or radio quiet, iii)to explain the subpulse drift phenomena adopting the space-charge limited ow model and comparingthe plasma drift velocity in the inner region of pulsar magnetospheres with theobserved velocity of drifting subpulses.

## Observability of Ancient Historical Solar Eclipses in East Asia

Ahn, Sang-Hyeon

Historical records on solar eclipses in the dynastic chronologies in East Asian history have been precious data to infer the rate of change of Earth’s rotation. However, modern calculations prove that a significant fraction of those records did not happen and that some of them had too small obscured fraction to be observed with bare-eyes. Even when the eclipse time and magnitude was given in a quantitative manner, those values do not agree with modern calculations. Hence, there has been dispute on whether they were predicted or really observed. Similarly, the totality of Ji-eclipses in ancient Chinese history has been suspected. Recently the concept of Ji-eclipse was proposed not to be exactly coincided with the modern terminology of total eclipse. Instead, it was pointed out that the eclipses whose magnitude were larger than ~0.8 were called as Ji-eclipses in the ephemeris calculations. Hence, additional descriptions such as daytime appearance of stars/planets, twilights, or arc-shaped solar disk are more concrete evidence on the totality of the eclipse records. Here in this poster the observability of ancient historical eclipse records was tested. In particular, the 1,200-year-long records, by 1000 CE, of both Chinese and Korean records were analyzed. We focused on the facts that solar eclipses can be recognized when the solar disk can be observed with bare-eyes when sun is setting or rising, and also that solar eclipse can also be observed with bare-eyes when the eclipse magnitude was nearly total. Considering atmospheric extinction, we checked the observability. As one consequence, the Korean records, having merely simple description that there was a solar eclipse and their date mostly overlapped with Chinese records and so having been suspected as being copied from Chinese chronologies, were proved to be original records of Korean astronomers rather than mere copy of Chinese records.

## X-ray variations of one changing-look quasar

Ai, Yanli

We report the changing-look quasar which went through a dramatic outburst, during which its X-ray flux increased by an order of magnitude after an increase of its optical/mid-infrared continuum flux. With the appearance of broad optical emission lines, this changing-look quasar provide us with important insights about the quasar physics.

## Multiple paths of deuterium fractionation in protoplanetary disks

Aikawa, Yuri

Molecular D/H ratios, such as HDO/H2O, are higher than the elemental D/H ratio in the primordial material in the Solar System, as well as in Earth’s ocean. This rather ubiquitous deuterium enrichment could originate in chemical reactions in cold environment such as molecular clouds and outer regions of protoplanetary disks, where the difference in zero-point energies between the normal and deuterated isotopologs stands out. While molecules are already deuterated in molecular clouds, the high D/H ratios of molecular ions indicate that deuteration proceeds in disks, as well. Spatial distributions of line intensities vary among deuterated species, which suggests that they have different deutration paths. Observations, however, show that their distributions also vary among disks. Motivated by these observations, we calculated a gas-grain chemical reaction network in protoplanetary disks to investigate the major deuteration paths and their dependence on disk parameters such as grain size and turbulence. Our network model includes spin-state chemistry, which is known to affect deuteration. We found multiple paths of deiuterium fractionation; exchange reactions with D atoms, such as HCO+ + D, are effective in addition to those with HD. If grains are small, freeze-out is severe in the cold midplane, while the disk surface is shielded from UV radiation to be relatively molecule-rich, which tends to make the radial distribution of molecular column density flat. As grains grow, photodissociation dominates in the disk surface, while gaseous molecules in the midplane are enhanced and contribute to line emissions. Turbulent diffusion transports D atoms and radicals at the disk surface to the midplane, and stable ice species in the midplane to the disk surface. The effects of turbulence on chemistry are thus multifold. We also derive the analytical formulas for abundances of H3+, HCO+, N2H+ and their deuterated isotopologues in the cold midplane.

## The Life of The Young Sun: Biogenic Conditions on the Early Earth and Mars

The physical environments of the young Sun can provide important clues for the origin of life on the early Earth and the potential for life on early Mars. According to recent observations of young stellar solar-like stars, our 0.7 Gyr-old Sun was a magnetically active star exhibiting frequent and energetic flares, coronal mass ejections (CMEs) and fast and dense wind, and thus extreme space weather environments. These extreme events should have impacted the atmospheres of the early Earth and Mars. In order to reconstruct space weather from the young Sun, we employed a data driven three-dimensional  magnetohydrodynamic Alfvén Wave Solar Model applied for k1 Cet, the best known young Sun’s proxy. Alfvén waves launched at the chromosphere dissipate into heat forming a hot and dense corona that emits intensively in EUV and X-ray bands and a fast and dense bi-modal wind.The fast wind emanating from the polar regions of the star interacts with slow wind associated with streamer belt and forms co-rotating interaction regions (CIRs) that develop into shocks. We also discuss our recent models of super-Carrington CMEs from the young Sun. The application of a 3D global magnetospheric models suggests that CME and CIR induced dynamic pressures and magnetic fields significantly perturbed the magnetospheres of the early Earth & Mars exposing 70% of their surfaces to energetic particles. Solar energetic particles accelerated on CIR and CME induced shocks could have contributed to the rise of prebiotic chemistry and the origin of life on these planets.

## Analysis of data modern astrometric catalogues in GAIA era.

Akhmetov, Volodymyr

The new big catalogues of proper motion were created using of GaiaDR1 data. The names of these catalogues are HSOY, UCAC5, GPS1 and PMA. Using three or more catalogues in Wielen method it is easy to estimate the external accuracy of each of them. The random errors of stellar proper motions had been calculated based on the common objects from HSOY, UCAC5, GPS1 and PMA catalogues. From a comparison of PMA data with same stars from the UCAC5, GPS1 and HSOY catalogues, the equatorial components of the mutual rotation vector of these coordinate systems were determined. The angular velocities of mutual rotation of the PMA and UCAC5, HSOY, GPS1 reference frames change within range from 0.2 to 2.0 mas yr-1. The estimation of systematic and random errors of the stellar proper motions of the PMA, HSOY and GPS1 catalogues in the faintest magnitude range had been done via an analysis of formal proper motions of extragalactic objects are containing in these catalogues. Also, comparisons of stellar proper motions of these catalogues with Gaia DR2 data was planned to carry out, when it will be released.

## Automated reduction of the photometric observations using CoLiTecVS

Akhmetov, Volodymyr

The main aim of the work is performing the automated reduction of the photometric observations in CCD-images during the variable stars research using CoLiTecVS. This is a new tool, which is able to do the following: images calibration using bias-, dark- and flat-frames, background alignment, inverse median filtration, stars identification, cross identification with astrometry catalogues, ensemble differential photometry. The result of CoLiTecVS processing is a light curve of the investigated object. The process is fully automated and can be run online during the observations. The method for estimating of brightness of the investigated star includes the following operations: selection of the comparison stars according to the proximity by distance, brightness and spectral class; excluding the comparison stars with anomaly error of instrumental brightness; calculating the brightness of the comparison stars and its reduction into the base frame; selection of the best combination of comparison stars by a minimum of the brightness RMS; calculating the brightness of the investigated star on the each frame. We've investigated the possible influence of non-linearity of median filtering on the photometry results. We didn't find measurable influence. Contrary – the background brightness equalization by inverse median filter usually provides better results as classical flat-field calibration. The photometry of constant stars obtained by CoLiTecVS was compared with the values obtained by conventional reduction process. We are working on the algorithm for automated processing to improve the photometric accuracy.

## Microlensing and time delays in gravitational lensed quasars

Akhunov, Talat

Gravitational lensing offers a unique tool to study the mass distribution of the lens, the structure of the light source as well as the physics of the Universe. However, any signi?cant contribution to these endeavours requires some continuous and detailed investigations of each known gravitational lens system. Therefore, we conducted optical monitoring of the gravitationally lensed systems H1413 + 117, B1422 + 237, PG1115 + 080, SBS1520 + 530, FBQ0951 + 2635 at the Maidanak Observatory in Uzbekistan for a long time. Thus, we obtained long-term series of observations, the photometric analysis of which gave us the following results.H1413+117: we analysed the V- and R-band light curves and V–R colour variations of the A–D components which show short- and long-term brightness variations correlated with colour variations. We have derived the new values of the time delays: ?tAB =-17.4 ± 2.1, ?tAC =-18.9 ± 2.8 and ?tAD = 28.8 ± 0.7 days (B and C are leading, D is trailing). We propose to characterize two kinds of micro-lensing events: micro-lensing for the A, B, C components corresponds to typical variations of ~10-4 mag/d during all the seasons, while the D component shows an unusually strong micro-lensing effect with variations of up to ~10-3 mag/d during 2004 and 2005.PG 1115+08: we found new values of the time delays in this GLS: ?tBA = 4.4±3.2, ?tAC = 12.0±2.5 and ?tBC = 16.4±3.5 days and that A1+A2 lensed components of the system might have undergone microlensing.B1422+237: we were able to get light curves for A,B and C lensed components which show us both activity of the source-quasar and presence of microlensing.FBQ0951+2635, SBS1512+530: we obtained light curves that show small-amplitude intrinsic variations of the quasar on time scales of about 100 days (in SBS1520+530). Variable magnitude di?erence between the images of the quasars shows the presence of microlensing variations in these systems.

## The 3D map astro/geo tour with your fingertips

Akihiko, Tomita

I present the example of the practice of the fingertip virtual tour of prefecture-level living area map and discuss future development of this activity. Once a year, I visit the half-day indoor activity for visually impaired children of mostly primary school ages, organized by a nonprofit organization “Picture Books for Visually Impaired and Weak Eyesight Children,” Osaka, Japan. This presentation is the report of the activity in 2017. I made 15 cm x 15 cm 3D map with height emphasized by five, 250 km x 250 km Kansai area in Japan using numerical data by Geospatial Information Authority of Japan. Using this 3D map as the mold, plaster replica was prepared for each of all the participants including about a dozen visually impaired children and their brothers and sisters, parents, and staff. Though the 3D printer has become common, it is still expensive and not easy to handle. The plaster replica making is easy and quite inexpensive. The 3D printer work was made in the university, and the plaster work was made by parents and activity staff on site. The Kansai area shows many rows of the north-south direction mountain ridges parallel to each other. This means that a great compression force is acting in the east-west direction on the plate of this area. We can understand why we have so many earthquakes in this area. The participants understand that planetary geological mechanism contributes to maintaining the Earth environment. Children shouted, “Interesting!” and parents enjoyed understanding the nature of the planet. We already have numerical map data around the world. Children can learn about other countries through their fingertip trip, which can help connect children across the borders of countries and language. We also have numerical map data of other worlds in the solar system. Children regardless of the eyesight can share the “grand tour” of the solar system and can understand each world’s nature and history by reading scientifically the surface information.

## Retention of Small Charged Dust in Planet Forming Disks

Akimkin, Vitaly

Dust evolution in disks around young stars is a key ingredient to the global disk evolution and accompanying planet formation. The mutual sticking of initially small grains is not straightforward and may be hampered by several processes. This includes dust grain bouncing, fragmentation, electrostatic repulsion and fast drift to the central star. In this study we aim at theoretical modeling of the dust coagulation coupled with the dust charging and disk ionization calculations. We show that the electrostatic barrier is a strong restraining factor to the dust coagulation in the micrometer size regime. While the sustained turbulence helps to overcome the electrostatic barrier, dust fluffiness limits its potential. Coulomb repulsion may keep a significant fraction of dust at 1-10um size range in vast regions of protoplanetary disks.

## NOC activities at Syria

The poster present the NOC activities at Syria

## M1-92 revisited: the chemistry of an ejected common envelope

Alcolea, Javier

M1-92, Minkoswi's Footprint, is a 0.9 Mo pPN around a B-type post-AGB source. Previous IRAM Plateu de Bure 13CO 2-1 observations showed that this nebula is the result of a brief but huge mass-loss event that occurred 1200 yr ago. Using the IRAM 30m MRT, we have have conducted a very sensitive spectral line survey of M1-92, the observations almost fully covering the 3mm, 2mm, and 1.3mm bands. We have detected, for the first time in this source, numerous molecular species such as HCN, HNC. CN. CS, NS, SiO, SO, SO2, H2S, including the cations HCO+, N2H+, and SO+. These species include tracers of PDR chemistry and of shock chemistry, indicating that both processes are presently active in the source. More recently, some of the detected lines have been observed with sub-arc-second resolution, using the IRAM NOEMA 9-element array. Combining single dish and (old and new) interferometric data, we have determined the abundance of the most relevant species in the different parts of the pPN. Most relevant, C17O and C18O observations suggest a very shocking result: the derived [17O]/[18O] ratio indicates that, according to standard nucleo-synthesis models, the initial mass of the central star was 1.8 Mo. This is in agreement with the high mass of the nebula, but in contrast with the relatively low [12C]/[13C] ratio and the O-rich chemistry of the source. We suggest that all these results can be reconciled if we assume that the copious mass loss event occurred 1200 yr ago, which resulted in the formation of the present nebula, was also responsible for the premature ending of the AGB phase of the star. This would have prevented the 3rd dredge-up to occur, and so the source would have escaped from its transformation into a carbon rich source. If this hypothesis this is correct, and depending on the prevalence of such events, we may have to revise our knowledge on stellar yields from AGB stars.

## Primordial Mass and Density Segregation in a Young Molecular Cloud

Alfaro, Emilio J.

We analyse the geometry of the Pipe Nebula, drawn by the distribution (Q-spatial parameter) and hierarchy (spatial segregation) of column density peaks previously detected and catalogued. By analysing the mass and volume density of the cores, we determine that both variables shown to be spatially segregated and highly structured. Given the early evolutionary state of the Pipe Nebula, our results suggest that both, mass and volume density segregations, may be primordial, in the sense of appearing in the early phases of the chain of physical mechanisms which conform the star-formation process. We also propose that volume density, and not mass, is the pararameter that most clearly determines the initial spatial distribution of the pre-stellar cores.

## Statistics of the relative orientation between magnetic fields in clumps and filaments

Alina, Dana

Star formation seems to be more efficient inside filamentary structures of molecular clouds. The role that the magnetic field plays in this process can be revealed using polarimetric data. We have performed a statistical analysis of the relative orientation between the plane-of-sky magnetic field and the filaments associated with the Galactic Cold Clumps - the very cold condensations of ISM that could host regions of star formation. We have separated polarization parameters components of the filaments and their background using thin optical medium assumption, and the filaments have been detected in the Planck data using the Rolling Hough Transform algorithm. Alignment properties depend on the density of the filaments but also on the density of the filaments’ environment. We find both parallel and perpendicular alignment between the matter structures and the magnetic field inside the Planck Cold Clumps situated in high density environments while there is mostly parallel alignment inside the filaments if the clumps contribution is omitted.

## The formation of massive binaries as a result of the dynamical decay of trapezium systems

Allen, Christine

We study the dynamical evolution of 10 multiple systems of trapezium type with very massive components.  As initial conditions we take the planar positions, transverse velocities, distances and masses from the best observations found in the literature.  Radial velocities and z-positions are not available, but were modeled by Monte Carlo simulations.  Our results show that the dynamical lifetimes for these systems are extremely short, shorter than the evolutionary lifetimes of their massive components.  Only assuming much larger masses for the components both lifetimes become comparable.  These results are similar to the dynamical lifetimes we found previously for the minicluster associated with the B component of the Orion Trapezium and for the Orion Trapezium itself. The end result of the simulations is usually  a close massive binary, sometimes a triple system.

## The relevance of old measures for studies of the dynamical evolution of trapezium systems

Allen, Christine

Studies of the internal motions in multiple systems are necessary to understand their dynamical evolution. Carefully selected historical measures of the separations and position angles have proved  to be important to construct dynamical evolution models of trapezium systems, because in spite of their relatively low accuracy, they provide a long time baseline.  We have successfully  used historical measures for such studies.  We discuss as examples the dynamical evolution of the Orion Trapezium, and that of ten additional massive trapezia with sufficient historical data.  We find extremely small dynamical lifetimes for all of these systems, comparable to those we found earlier for the minicluster associated with the B component of the Orion Trapezium.

## FORTY-FOUR YEARS OF REVISTA MEXICANA DE ASTRONOMIA Y ASTROFISICA: ITS IMPACT ON THE LATIN AMERICAN ASTRONOMICAL COMMUNITY

Allen, Christine

After 44 years of continuously publishing the Revista Mexicana de Astronomía y Astrofísica, we cast a short retrospective view on its history emphasizing its regional impact.RMxAA was founded in 1974. The journal has published original research papers in all areas of astronomy, astrophysics and related fields. Until 1994 RMxAA also published the proceedings of astronomical conferences held in Mexico and Latin America. Since 1995 a Series devoted exclusively to such proceedings was founded, RMxAC, Revista Mexicana de Astronomía y Astrofísica Serie de Conferencias.All papers submitted to RMxAA are strictly refereed. RMxAA is included in the most important international indexes. Both publications are fully integrated into the ADS. Their contents have always been freely available to the general public. This ensures a wide international visibility, comparable to that of the best astronomical journals.The impact factor of RMxAA has varied over the years, mostly as a consequence of small number statistics. The average impact factor is about 2.4, greater than that of all but a few Latin American scientific journals.The editorial independence of RMxAA, the fact that there are no page charges for authors, and that the printed version is distributed free of charge to astronomical libraries all over the world has contributed to the development of astronomy, especially in Latin America.  The Conference Series has published the proceedings of IAU Latin American Regional Meetings (LARIM), as well as those of Astronomía Dinámica en Latino América (ADeLA) and other astronomical meetings in the region,  thus stimulating regional astronomical development and collaboration.

## Improving your research reproducibility with the Astrophysics Source Code Library

Allen, Alice

Astrophysics research relies on software and all robust science requires transparency and reproducibility, yet the computational methods used in our discipline are often not shared or are difficult to find. In recent preliminary research, 40% of the software used in the 2015 papers we examined did not offer source code and restricting the reproducibility of this research. The Astrophysics Source Code Library (ASCL. ascl.net) registers astrophysics research source codes that have been used in refereed research, benefiting the field in numerous ways, including increasing the discoverability of software and making the published research record more robust. With over 1,700 codes, the ASCL is the largest indexed resource for astronomy research codes in existence. This free online registry was established in 1999 and is indexed by ADS and Web of Science. ASCL registration allows your software to be cited on its own merits and provides a citation method that is trackable and accepted by all astronomy journals and journals such as Science and Nature. This presentation covers the benefits of registering astronomy research software with the ASCL, upcoming changes that will enable greater software discovery initially for NASA software and potentially for software funded by other organizations, changes to the ASCL and ADS that benefit researchers, and our research into software use in astronomy.

## Revisiting the solar flux predicted by model photospheres

Allende Prieto, Carlos

One of the big successes of the theory of model atmospheres is the ability of models to approximately reproduce the observed disk-integrated solar flux from the near-UV to the mid-infrared. In this presentation I will present recent calculations to quantify how good this agreement is for state-of-the art theoretical models of the solar photosphere.

## The cold gas reservoir feeding a distant interacting young radio galaxy

Allison, James

While some radio galaxies show stong emission lines in the optical, characteristic of an active galactic nucleus (AGN), others do not. We have substantial circumstantial evidence that this dichotomy is the result of the mode in which gas is accreted onto the nucleus. However, the exact mechanisms by which high and low excitation radio galaxies are nourished can only be determined through direct observation of the gas. A powerful method for measuring the kinematics of gas deep into the centres of radio-loud AGN is through detection of the HI 21-cm hyperfine and CO rotational lines in absorption. The Australian Square Kilometre Array Pathfinder (ASKAP), in its commissioning and early science phase, has been very successful in detecting HI absorption in powerful radio galaxies at intermediate cosmological redshifts. In followup observations using ALMA we have detected 12CO(2-1) absorption in PKSB1740-517, a young luminous radio galaxy at z=0.44 that has likely undergone a recent interaction with its companion galaxies. I will discuss the results of this work, including how we can disentangle the line-of-sight ambiguities from absorption and what we learn about the system by combining the ASKAP, ALMA and multiwavelength ancillary data.

## Investigating Transient Events in Active Stars

Stellar magnetic fields completely dominate the environment around late-type stars. They are responsible for driving the coronal high-energy radiation (e.g. EUV/X-rays), the development of stellar winds, and the generation of transient events such as flares and coronal mass ejections (CMEs). While considerable progress has been made for the first two processes, our understanding of the eruptive behavior of active stars is still very limited. This information is critical as these phenomena can have a strong or even catastrophic impact on planetary systems. This is of particular importance during the early stages of evolution where they can become the dominant factor in determining the physical properties around late-type stars. In this context, I will present the initial results of a joint observational and numerical project, aimed at studying the properties of eruptive phenomena in active stars. The first aspect comprises the analysis of simultaneous observations of X-ray and white light flares of young stars, acquired with the Chandra and Kepler (K2) telescopes. On the numerical side, I will present detailed 3D MHD simulations of CMEs in active stars, developed using one of the latest models employed for space weather forecasting in the solar system. These results will be discussed in the general solar-stellar context, taking into account the observed properties of the magnetic fields in which they develop.

## Far Beyond the Sun: Mapping the Magnetic Cycle of the Young Solar-Analog iota Horologii

A former member of the Hyades cluster, iota Horologii (? Hor) is a ~625 Myr old Sun-like star which displays the shortest coronal activity cycle known to date (PCYC ? 1.6 yr). Apart from the Sun, this X-ray activity cycle is also the only one identified on a single star so far. The link between the activity cycles and the characteristics of the surface magnetic field is a fundamental piece of information to understand the origin of stellar magnetism in late-type stars. Here we present the initial results of a long-term observing campaign aimed at studying the evolution of the magnetic cycle of ? Hor, using ground-based high-resolution spectropolarimetry. Using the technique of Zeeman Doppler Imaging (ZDI), we have successfully detected non-simultaneous large-scale polarity reversals associated with the azimuthal and the radial components of the magnetic field, over the course of the activity cycle of the star. Moreover, using state-of-the-art 3D Magneto-Hydrodynamics (MHD) simulations, each recovered ZDI radial field map help us to self-consistently model the coronal structure, stellar wind, and astrospheric conditions around the star. These models will be compared with simultaneous X-ray monitoring of the corona using XMM-Newton (AO-16), and with stellar wind diagnostics from HST (Cycles 25 & 26).

## Galactic context to local star formation: the local neighborhood in the Gaia era

Alves, Joao

Gaia will revolutionize our view of the local galactic neighborhood not only for the precise measurements of its stellar content but also for the exquisite 3D view of the local ISM. In this contribution, I will focus on the interplay between local massive stars and molecular cloud complexes (d < 500 pc) where resolved star formation can be studied, from dense core formation to circumstellar disk dissipation. We will start by describing the newly discovered Blue Streams, their validation from ground-based spectroscopic data and Gaia data, and how these streams are impacting the structure of both the diffuse and dense star-forming ISM. We will present Herschel maps of the nearby complexes and show evidence that stellar feedback from the streams plays a fundamental role not only in assembling but also shaping filaments and cores, as well as driving most of the observed turbulence. We will argue that the Blue Streams, because of their massive star content proximity to Earth, can have an impact on life on the planet. I will end by pointing to a large NIR survey of the local complexes carried out in Vienna (VISIONS visions.univie.ac.at) that together with Gaia data will allow for the first 3D space motion map of the local star-forming ISM, opening a new window on ISM dynamics.

## The detailed chemical abundance pattern of the metal-rich Galactic globular cluster NGC 6366

Alves-Brito, Alan

Globular cluster (GC) stars have been known to display chemical inhomogeneities (multiple populations) in their light elements (Li, CNO, Na, Al, Mg and F). While this chemical pattern is likely primordial, there is no consensus about the nature of the polluters, with intermediate-mass Asymptotic Giant Branch (AGB) stars, fast rotating massive stars, massive interacting binaries and supermassive stars being some of the candidates. In this work, we present chemical abundances for a sample of eight red giants in the metal-rich GC NGC 6366, which has been little studied in the literature. We have used high quality data (R > 40,000; S/N > 60) obtained at the VLT (8.2 m) and CFHT (3.6 m) telescopes. The abundances for light and heavy elements were obtained through equivalent widths and spectrum synthesis of individual atomic lines, using the MOOG stellar line analysis program, together with 1D Kurucz’s stellar atmosphere models. The derived abundances were compared with those obtained for stars in different environments (field and GCs). Our outcomes suggest that NGC 6366 is a monometallic GC ([Fe/H] = -0.60 ± 0.03), presenting a very short extension in its Na-O anticorrelation. After taking literature’s results into account, the Na-O diagram shows a barely detectable, if any, Na-O anticorrelation. Also, there is no evidence of Mg-Al anticorrelation and no star-to-star variation in Al in our sample. Abundance ratios of heavier elements, as Ba and Eu, as well as the similarities between the [Eu/Fe] and [a/Fe] ratios, lead us to believe that the primordial composition of NGC 6366 is dominated by objects with short time-scale, likely Type II SNe, with mild contribution of AGBs. None of the elements measured present star-to-star variation greater than the uncertainties, which means that NGC 6366 is chemically homogeneous.

## Explorers of the Universe: university and school creating new pathways.

Alves-Brito, Alan

The project “Explorers of the Universe: university and school creating new pathways" is an Outreach Program (popularization and scientific communication) from the Department of Astronomy of the Institute of Physics at the Federal University of Rio Grande do Sul, in Porto Alegre, Brazil. Launched in 2012, the project has an interdisciplinary, interinstitutional and interprofessional character. The goals are twofold: (i) to promote the training of Physics undergraduate students, especially future teachers of the Brazilian basic education system and (ii) to contribute to the scientific literacy of school students of Porto Alegre and its Metropolitan Region. The program is focused on young people living in regions of high social and economic vulnerability. It intends to improve the quality of education and to articulate the school-university dialogue by proposing new educational public policies. Workshops and activities promoted by the Program aim to integrate the outreach actions to the teaching and basic research programmes at the University, where undergraduate students have the opportunity of creating and executing thematic workshops. The Program encourages undergraduate students to:  practice creative thinking through science; develop the passion for the dark-sky observing; and develop scientific argumentation alongside different agents (teachers, school managers, pedagogues, social workers) in formal and non-formal learning environments.

## Astronomy for Development in Brazil: education and the intersection of gender, race, ethnicity and class in STEM.

Alves-Brito, Alan

Brazil is Latin America’s largest country in area and one of the most populous countries in the world, with approximately 210 million people. It is also a former Portuguese colony, displaying a highly diverse population that includes indigenous, descendants of African slaves and European settlers. Brazil accounts for approximately 90% of the world’s population who speaks Portuguese. For more than 350 years, the country was the focus of a strong Atlantic slave trade, importing more enslaved Africa people than any other country and being the last country in the Western world to abolish the slavery system. South America’s most influential country, Brazil presents a strong economic power. However, throughout its history, Brazil has been a country with a high level of inequality.  Over the past few years it has made major strides in its efforts to raise millions out of poverty, but the gap between rich and poor remains high. In this work, I will discuss how Astronomy, which is a multidisciplinary field, can fascinate people of different ages and cultures, occupying a prominent place among the basic sciences to guarantee global development in the 21st century. I will show and discuss how some of our projects in Brazil, focused on Educational Astronomy, are changing the reality in this country by promoting the intersection of gender, race, ethnicity and class in STEM (science, technology, engineering, and math) fields.

## Analysis and Design of a Prototype Low Frequency Radio Telescope

Aminaei, Amin

Radio astronomy is generally linked to the massive giant dishes while an important part of discoveries and breakthrough sciences is actually achieved by small low-frequency radio telescopes. At the selected frequency band, tens of MHz, the structure of antenna is light-weight and the physical size of the antenna is in the order of meters. Also, the analog and digital modules are commercially available and data processing can be done at low cost. Using a commercial digital board and compact analog module including an optimized antenna, analysis and design of a prototype low-frequency radio telescope is proposed. The radio telescope consists of a co-centered orthogonal antenna with extendable arms being capable of basic radio interferometry. It can be used as a stand-alone station where basic radio astronomy and atmospheric observations are feasible. Atmospheric phenomena such as scintillation and monitoring Sun and giant planets would be typical case studies. It can be also used as an ad-hoc element of a large-based array of the radio interferometrs at the same frequency band for fundamental astronomy observations. * Please also consider the presentation  for Focus Meetings: FM15, Astronomy for Development  whichever is more relevant

## An update on the progress of the SKA band 5 feed system

Aminaei, Amin

In accordance with the global effort for the development of the Square Kilometer Array (SKA) dish prototype, we report on the current status of the SKA band 5 Single Pixel Feed (SPF) system. The SKA band 5 is initially designed for the frequencies of 4.8-15.3 GHz and it’s been proposed to expand the upper limit to 25 GHz and higher which suits the study of the planet formation and exobiology. The performance of critical components of the prototype SPF is currently being validated. A prototype of the cryostat has been manufactured and the cryogenic system is being tested. It should maintain the temperature at the level of 20 K while connected to the heat load of the horn feeds. Also, we address the corresponding RF chain measurements, EMI testing, and progress on the development of a digital Feedback Package Controller (FPC) for SPF band 5 system.-On behalf of the SKA Oxford Team

## Deep high-resolution imaging of the field around nearby stars of the Ursa Major moving group

Ammler-von Eiff, Matthias

Results from a search for low-mass companions in the vicinity of 20 nearby Ursa Major group members are reported. The Ursa Major open cluster is the nucleus of this group and coincides with the Big Dipper constellation. Other members are spread over the entire sky and share a common space motion. The selected targets of high proper motion pass the background field quickly so that any comoving companion could be identified easily. The targets are also nearby and young so that low-mass companions would be bright in the near-infrared and separated well from the stellar image. The observations were taken with NAOS-CONICA at the ESO VLT in the Ks band using a semi-transparent coronagraph. The consolidated results of this survey have been published recently.The survey achieved a brightness contrast of typically 13-15 mag and was sensitive to objects as faint as 20 mag at separations between a few arcseconds and up to 25 arcseconds from the star. This is as close as several astronomical units for the nearby eps Eri and up to 600 au and more for the most distant targets. More than 200 faint background sources were identified. We will discuss the observations in the light of similar ground-based direct imaging campaigns and other recent studies of the UMa group.High-resolution imaging is not only a key technique to detect giant planets in wide orbits around nearby stars but is also essential for the follow-up of transit candidates from missions like TESS and PLATO. These monitor wide fields at low spatial resolution so that additional observations are needed to distinguish contaminating sources close to the actual targets. Even though NAOS-CONICA has already been decommissioned, the results presented are considered relevant to the ground-based follow-up of TESS and PLATO targets as those will be bright, potentially nearby, and may display significant proper motion.

## Flybys versus Mergers: Contributions to the Spin-Orbit Alignment of Dark Matter Halo Pairs

An, Sung-Ho

Recent observations reveal that the spin of a galaxy is often aligned with the orbital angular momentum of its companion. Using cosmological N-body simulations, we investigate the relative contributions of the merger and flyby to the spin-orbit alignment of galaxy pairs. We examine a sample of dark-matter halo pairs with the similar masses to the Milky Way (11.6 < Log Mhalo/Msun < 12.4), the mass ratios from 1:1 to 1:3 (major interactions), and the separations smaller than a sum of their virial radii (R12 < R1,vir + R2,vir). The result shows that the dark-matter halo has its spin preferentially aligned with its companion’s orbital angular momentum (i.e., the prograde interaction), corroborating previous studies. We find that while both the merger and flyby interactions lead to the increase in the angular momentum of galaxies, mergers make a greater contribution than flybys, leaving stronger spin-orbit alignment (fprograde = 0.75) than flybys (fprograde = 0.60).

## Metallicity Mapping of the Milky Way with Large Photometric Surveys

An, Deokkeun

We present a metallicity map of the Milky Way Galaxy within 10 kpc from the Sun, based on extensive sets of ugriz photometry from the Sloan Digital Sky Survey (SDSS), the Southern Galactic Cap u-band Sky Survey (SCUSS), and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). We obtain metallicities for individual stars by applying a set of stellar isochrones, which have been calibrated against observations of main-sequence stars in clusters and  tested using spectroscopic data. Our metallicity scale has been further checked using Gaia priors for relatively nearby stars. Our metallicity map has a continuous spatial coverage and thus is less susceptible to sampling bias, and can be used as an independent check on results from recent spectroscopic survey data. Combining with proper motion measurements from Gaia, our metallicity estimates reveal a long tail of stars with retrograde rotation in the Galactic halo. These stars exhibit systematically lower metallicities than those in prograde rotation, consistent with previous findings based on smaller photometric data samples.

## Sub-galactic regions on the galaxy-wide scaling relations: the example of the ULX-rich galaxies NGC 3310 and NGC 2276

Anastasopoulou, Konstantina

We present results from Chandra observations of the X-ray starburst galaxies NGC 3310 and NGC 2276. We detect 30 discrete sources with luminosities above 2.0x1038 erg/s in NGC 3310, and 19 discrete sources with luminosities above 1.0x1038 erg/s in NGC 2276. The majority of the sources have photon indices of 1.7-2.0, typical for X-ray binaries. Both galaxies have large numbers of ultra-luminous X-ray sources (ULXs): 14 for NGC 3310 concentrated on the circumnuclear star-forming ring and north spiral arm, and 11 for NGC 2276 with the brighter ones on the west side of the galaxy which is compressed due to harassment by the intra-group medium it is moving into. We find for both galaxies that the ULX-hosting areas show excess X-ray luminosity with respect to the general scaling relations between X-ray binary luminosity, SFR, and stellar mass. On the other hand, other regions of the galaxies either agree or fall below these scaling relations. This indicates that sub-galactic regions do not necessarily follow the galaxy-wide scaling relations. The significant deviation from the average galaxy-wide scaling relation can be attributed to either age or metallicity variations between sub-galactic regions, with the former being more likely. Such differences in age could be the origin of the scatter we observe in the low SFR regime of the LX-SFR scaling relations.

## Carbon Enrichment in the Early Universe

Andersen, Johannes

Carbon-enhanced extremely metal-poor (CEMP) stars are our richest source of information on carbon (C) in the early universe. CEMP stars are of two basic varieties, with or without enrichment of elements synthesized by the slow neutron-capture process – CEMP-s and CEMP-no stars; each is associated with the inner and outer (most metal-poor; [Fe/H] < -3.5) halo populations, respectively. Canonically, CEMP stars were considered to be the result of local binary mass transfer, and much effort was invested in models according in this paradigm. However, Hansen et al. (2016a,b) showed that only ~80% of the CEMP-s stars are binaries, the CEMP-no stars and ~20% of the CEMP-s stars were single. Thus, C in these stars has been synthesised in a different object and implanted across interstellar space in the natal clouds of today’s CEMP stars, and both fast-rotating primordial stars and ‘faint’ supernovae have been invoked as possible progenitors. In a recent review, however, Höfner & Olofsson (2018) discuss whether combined radiation and pulsation pressures could eject C dust from a single star, obviating the need for a binary companion. Spectroscopic log g-s are uncertain for CEMP stars, so there is doubt if they are ‘normal’ giants or AGB stars. Gaia DR2 should yield actual log L values to tell, and the photometry should have sufficient precision and time coverage to confirm or refute the reality of the 3-400-day pulsations suggested by earlier radial-velocity work.

## Binary Population Synthesis with Markov-chain Monte Carlo

Andrews, Jeff

Nowhere is our understanding of binary evolution challenged more than in the formation of the merging double neutron stars (DNS) recently detected by gravitational wave observatories. Yet, exactly because these systems are so sensitive to binary evolution physics, they have the most potential to constrain theory. These constraints are traditionally placed using binary population synthesis, a method that, despite its potential, has difficulty generating sufficient statistics because merging DNSs are exceedingly rare; only a small fraction of simulated systems evolve into binaries similar to those observed. I will introduce a fundamentally new approach to studying stellar binary populations that employs a Markov-chain Monte Carlo algorithm to efficiently explore the binary evolution parameter space. In addition to being substantially more efficient than traditional methods for studying high mass binaries, this technique seamlessly incorporates observational constraints and their corresponding uncertainties. As a test case, I apply this method to model the population of high mass X-ray binaries in the Large Magellanic Clouds. Finally, using this approach I will demonstrate what we can learn about the formation and evolution of the merging compact objects detected by LIGO.

## RAMSES II - Raman Search for Extragalactic Symbiotic Stars

Angeloni, Rodolfo

Symbiotic stars (SySt) are long-period interacting binaries composed of a hot compact star - generally a white dwarf (WD) - an evolved giant star, and a tangled network of gas and dust nebulae. SySts represent unique laboratories for studying several astrophysical phenomena and their reciprocal influence. They are also among the most promising candidates as progenitors of SNIa.Presently, we know 252 SySt in the Milky Way and 62 in external galaxies. However, these numbers are still in striking contrast with the predicted population of SySt in our Galaxy that, according to different estimates, may oscillate between 10^3 and a few 10^5. The actual SySt population is thus a key issue that needs further investigating.One of the reasons for this embarrassing discrepancy between SySt population synthesis models and observations also stems from the fact that the SySt group has been historically defined on the basis of purely spectroscopic criteria. Because of many other stellar sources mimicking SySt colors, no photometric diagnostic diagram has so far demonstrated the ability to unambiguously identify a SySt, thus making the recourse to costly spectroscopic follow-up still inescapable.The two intense Raman OVI bands at 6830Å and 7088Å, however, are so unique to the symbiotic phenomenon that their presence is considered a sufficient criterion for classifying a star as symbiotic, even when the donor star is not directly visible through optical spectroscopy. In this poster we present the early results from RAMSES II (Raman Search for Extragalactic Symbiotic Stars), a Gemini/GMOS Upgrade Project funded by AURA, which makes use of the Raman OVI 6830Å band as a powerful photometric tool to identify new SySt within and beyond the Galaxy.

## Youth Engagement with Astronomy

Anjos, Sara

Science communication research has raised multiple questions about the interaction between science and the public. Some concern the production of scientific knowledge in context, whereas others are related to how knowledge is transposed, transferable and rebuilt, depending on individual and social needs and experiences, and on the representations of science each individual or public group has, to mention just a few.Clarifying these and other questions that have arisen in the Science-Technology-Society (STS) field is without any doubt important, as science (and its applications) occupies a crucial place in society and in the way people live and understand the world.One of the recurring themes is how the public understands and engages with science, based on science literacy studies and their implications in the promotion of public participation in Science and Technology (S&T) decisions. Constructivist research has problematized science and processes of knowledge production by examining how people experience science in their lives and how scientific achievements are embodied in social relations. On the basis of such reasoning, alternative forms of problematizing science literacy have emerged.This research falls within that approach, by carrying out a study to evaluate Science Communication and Informal Science Education activities, focusing on the astronomy field. Particularly for the youngest, one of the aspects highlighted in the discussion about the relationship with science is fundamentally implicated on the design of a common social future, which implicates choices as consumers, the aspiration to academic and professional careers and participation on public life, as citizens.

## Orientation of the spins of thin galaxies

Antipova, Aleksandra

We present a preliminary analysis of the orientation of the spins of edge-on galaxies relative to the elements of the large-scale structure of the universe, such as groups, clusters and filaments of galaxies. In this work, we use the Revised Flat Galaxy Catalog, compiled by Karachentsev I.D. et al. (1999). This catalog contains 4236 flat galaxies with an axes ratio greater than 7. This allows us to identify galaxies of late types (Sc, Sd) visible from the edge. For edge-on galaxies, we can determine the orientation of the spin with high accuracy. Currently at the 6-meter Russian Telescope (BTA - Big Telescope Alt-azimuth) we study the rotation curves of 160 superthin edge-on galaxies. The program is fulfilled on 70%. From these data we determine the angular momentum and examine the orientation of the spins of galaxies relative to the surrounding structures.

## Thermal conductivity of porous dust aggregates

Arakawa, Sota

The thermal conductivity of dust aggregates is a key parameter in planetary science, including thermal evolution of minor planets and comets. However, the porosity dependence of thermal conductivity for highly porous aggregates is not yet thoroughly understood.We numerically investigated the thermal conductivity of fluffy dust aggregates. In our calculation, we used the snapshot data of N-body simulations of static compression in the periodic boundary condition and determined the temperature structure and heat flux of the porous dust aggregates.We derived an empirical formula for the solid thermal conductivity as a function of the filling factor of dust aggregates. The results reveal that the solid thermal conductivity is approximately proportional to the square of the filling factor. For the case of dust aggregates with the filling factor in the range of 0.1-0.5, our results are well consistent with the experimental data. Moreover, we also found that the solid thermal conductivity is significantly lower than previously assumed for highly porous aggregates whose filling factor is lower than 0.1. In light of these findings, we will reexamine the thermal histories of small planetary bodies.

## Astronomy in Serbia and Serbia in the International Astronomical Union

Arbutina, Bojan

We briefly discuss the history of membership and the current position of Serbia inside the International Astronomical Union. We give an overview of astronomy education, research and public outreach in Serbia. Some statistics is presented concerning the number and gender of BSc, MSc and PhD students that graduated/obtained their degree in astronomy/astrophysics from the Department of Astronomy, Faculty of Mathematics, University of Belgrade. Due attention is paid to the most important scientific/educational institutions in Serbia in which the majority of astronomers are employed as well as various research topics investigated.

## Mildly Super-Eddington mode of X-ray pulsars

We consider observational appearances of several X-ray pulsars and discuss possible application to the modern models of  X-ray emission generation in accreting pulsars with strong magnetic field.  In particular we consider the arising limitations on properties of accretion column, based on found results.

## Oxygen abundance gradients in nearby galaxies and the performance of strong-line methods

Arellano-Córdova, Karla Ziboney

We study the abundance gradients implied by the direct, temperature-based, method and several strong-line methods using optical spectra obtained by different authors for H II regions in the galaxies M31, M33, M81, M101, and NGC 300. We find that the direct method and the P method introduce large dispersions around the gradient, of 0.11-0.25 dex, whereas the ONS, C, O3N2, and N2 methods lead to lower dispersions, in the range 0.06-0.11 dex. The differences in dispersion can be explained by considering the sensitivity of each method to line ratios such as [O II] 3727/Hbeta and [N II] (6548 + 6584)/5755, which are susceptible to observational problems. In those galaxies that have better determinations of the oxygen abundance gradient with the direct method, the C method provides gradients that are more consistent with the ones based on this method. We explore further the performance of strong-line methods using a sample of 168 spectra of H II regions with measurements of two temperatures, Te[N II] and T[O III], compiled from the literature. We confirm that the C method provides better estimates of the oxygen abundance, with differences with respect to the direct method that are lower than 0.2 dex for most of the objects in the sample. The other strong-line methods introduce larger differences and a dependence of these differences on the degree of ionization. Finally, we analyze the temperature structure of our sample of H II regions and derive a new set of temperature relations between Te[N II] and T[O III], which can be used whenever one of these temperatures is not measured.

## TolTEC: a large-format polarimetric millimeter imaging camera for the 50m Large Millimeter

Aretxaga, Itziar

TolTEC a large-format (~7000 detector) imaging polarimeter in construction for the 50m Large Millimeter Telescope, is the result of a consortium of 7 institutions in the USA, Mexico and the UK. TolTEC will provide the capability to conduct surveys at 1.1, 1.4 and 2.1mm and detect point-like and extended sources in large areas ranging to hundreds of square degrees to unprecendented depths. Here we present a review of the construction status and plans to conduct four legacy surveys, starting in 2019: The Clouds-to-Cores Legacy Survey that explores the collapse of giant molecular clouds into star-forming cores ; The Fields in Filaments Legacy Survey is designed to probe the distribution of magnetic fields in filaments as traced by the polarization of dust; The Ultra-Deep Survey of Star-forming Galaxies is a confusion-limited survey which ties the entire Luminous Infrared Galaxy population from redshifts 2 to 10 directly to their optical counterparts; and The Large Scale Structure Survey probes the relationships between the spatial distribution of star forming galaxies and large scale structure and provides a detailed view of clusters and their substructure via the Sunyaev-Zeldovich (SZ) effect.

## Observing in the past thanks to the Gaia astrometric reference star catalogue

Arlot, Jean-Eudes

The arrival of the Gaia astrometric reference star catalogue is not only a giant step in the astrometric accuracy allowing to measure new unknown small motions of solar system objects but also to observe in the past with today accuracy. In fact, accurate astrometry is performed since about one century after the use of photographic plates. The measures made at the time of the old observations used old reference catalogues, the accuracy of which being between 500 mas and one arcsec. We will show how we are making new measures and new reductions of photographic plates thanks to the Gaia reference catalogue allowing to provide valuable data and pre-discoveries of recently observed objects.

## The ephemerides and astrometric database for natural planetary satellites

ARLOT, Jean-Eudes

The former working group “Motions and observations of the planetary satellites” fulfilled its tasks and all astrometric observations together with several ephemerides are now provided to the astronomical community. However, some problems are not solved: the databases of observations are in different format contrarily to the asteroid database which adopted a standard format. In spite of the different sources of types of observations, it will be useful to choose a standard format (linked with VO) in order to make easier the research for improving the dynamical models and ephemerides. A discussion should be made in Division A and Commission X2 Ephemerides to decide on standards to be applied in the future.

## Understanding internal structure of planetary satellites through astrometry

ARLOT, Jean-Eudes

The internal structure of the natural planetary satellites have an influence on the motion of these objects. Careful observations may lead to constraints on this structure. However, in spite of the high accuracy of recent space probe observations, the observations are not made on a sufficient interval of time to put into evidence the effects due to the internal structure. These effects are cumulative and we need long period observations. In order to solve that problem, we digitized old photographic plates and reduced them with the Gaia reference star catalogue providing old data with today accuracy. This method is very promising for the understanding of the formation, evolution and structure of the natural planetary satellites.

## Sloshing in its cD halo: MUSE kinematics of the central galaxy NGC 3311 in the Hydra I cluster

Arnaboldi, Magda

We aim to identify the main structural components of the Hydra I cD galaxy NGC 3311 to investigate the connection between the central galaxy and the surrounding stellar halo. We produce maps of the line-of-sight velocity distribution (LOSVD) moments from a mosaic of MUSE pointings covering NGC 3311 out to 25 kpc. Combining deep photometric and spectroscopic data, we model the LOSVD maps using a finite mixture distribution, including four non-concentric components that are nearly isothermal spheroids, with different line-of-sight systemic velocities V, velocity dispersions σ, and small (constant) values of the higher order Gauss-Hermite moments h3 and h4._x005F The kinemetry analysis indicates that NGC 3311 is classified as a slow rotator, although the galaxy shows a line-of-sight velocity gradient along the photometric major axis. The comparison of the correlations between h3 and h4 with V/σ with simulated galaxies indicates that NGC 3311 assembled mainly through dry mergers. The σ profile rises to ≃ 400 km s-1 at 20 kpc, a significant fraction (0.55) of the Hydra I cluster velocity dispersion, indicating that stars there were stripped from progenitors orbiting in the cluster core. The finite mixture distribution modeling supports three inner components related to the central galaxy and a fourth component with large effective radius (51 kpc) and velocity dispersion (327 km s-1) consistent with a cD envelope. We find that the cD envelope is offset from the center of NGC 3311 both spatially (8.6 kpc) and in velocity (ΔV = 204 km s-1), but coincides with the cluster core X-ray isophotes and the mean velocity of core galaxies. Also, the envelope contributes to the broad wings of the LOSVD measured by large h4 values within 10 kpc. We conclude that the cD envelope of NGC 3311 is dynamically associated with the cluster core, which in Hydra I is in addition displaced from the cluster center, presumably due to a recent subcluster merger.

## Observational Properties of Miras in the KELT Survey

Arnold, Robert

We present a catalog of the observed properties of Mira variable stars detected with the KELT survey.  Asymptotic giant branch (AGB) stars were identified in KELT using their 2MASS and WISE colors, and their variability properties were determined from KELT data. Of the 21279 KELT AGB objects, over 700 Mira variables were identified.  Here we present their observed periods, luminosities, and temperatures that will place important constraints on future theoretical work on the effect convection has on pulsation periods and stability.

## PERTURBING EFFECTS OF CORIOLIS AND CENTRIFUGAL FORCES IN THE RESTRICTED FOUR-BODY PROBLEM WITH ALL OBLATE PRIMARIES

Arora, Monika

The present paper explores the e ect of the perturbations of Coriolis and Centrifugal forces in the restricted four-body problem when all the primaries are oblate in the Lagrange equilateral triangle con guration. We have numerically investigated the number of libration points, viz. the in-plane and out of plane and investigated their stability. Zero velocity curves have also been drawn and the regions of motion have been explored for various values of the Jacobi constant. Newton Raphson basins of attraction have also been drawn and investigated.

## The role of metallicity in high mass X-ray binaries

Artale, Maria Celeste

In the last decade, different observational and theoretical studies indicate that the number and X-ray luminosity of high mass X-ray binaries (HMXBs) are directly correlated with stellar metallicity. Previous work claims that metal-poor progenitors are more likely to produce brighter HMXBs.  In this work, we test this correlation with metallicity by using population synthesis models and exploring the mechanisms that may produce this dependence.  We also investigate the HMXBs population in galaxies by implementing the results from population synthesis models into the galaxy catalogs from state-of-the-art galaxy formation models.

## The chemical fingerprint of Class I sources

Artur de la Villarmois, Eizabeth

The formation and evolution of protoplanetary disks are a fundamental ingredient in the process oflow mass star formation. In particular, Class I sources act as a ‘bridge’ between the deeplyembedded Class 0 sources and the emergence of protoplanetary disks, associated with Class IIsources. Thus, the study of Class I sources are of prime importance for our understanding of theformation and evolution of solar-type stars and their disks.In this work, we present an ALMA chemical survey of 10 Class I sources in Ophiuchus. Thecovered molecular transitions were chosen specifically to trace the kinematics of disk formation(i.e., C17O, H13CO+ and C34S) and the warm chemistry in the inner envelope or disk (i.e., SO2and CH3OH). The tracers reveal the chemistry and physics of the embedded disks, probing materialwith high temperatures and densities. In spite of a very high sensitivity, CH3OH is not detectedtoward any of these sources. This suggests that CH3OH gas only exists in a very thin layer betweenbeing frozen out as ice and photo-dissociated by UV radiation from the star. Furthermore, we findthat SO2 shows compact emission and the intensity correlates with the luminosity of the sources.Therefore, SO2 may be a better tracer of the warm gas and its associated chemistry in these sources.These observations show the existence of disk-like structures, associated with most of the sourcesof the sample, and highlight the differences in the physical structures between Class I sources andother stages of low-mass star formation.

## A Study of Inner Disk Gas around Young Stars in the Lupus Complex

Arulanantham, Nicole

We present a study of molecular hydrogen at the surfaces of the disks around five young stars in the Lupus complex: RY Lupi, RU Lupi, MY Lupi, Sz 68, and TYC 7851. Each system was observed with the Cosmic Origins Spectrograph (COS) onboard the Hubble Space Telescope (HST), and we detect a population of fluorescent H2 in all five sources. The temperatures required for LyA fluorescence to proceed (T ~ 1500-2500 K) place the gas within ~15 AU of the central stars. We have used these features to extract the radial distribution of H2 in the inner disk, where planet formation may already be taking place. The objects presented here have very different outer disk morphologies, as seen by ALMA via 890 micron dust continuum emission, ranging from full disks with no signs of cavities to systems with large regions that are clearly depleted (e.g. TYC 7851, with a cavity extending to 75 and 60 AU in dust and gas, respectively). Our results are interpreted in conjunction with sub-mm data from the five systems in an effort to piece together a more complete picture of the overall disk structure. We have previously applied this multi-wavelength approach to RY Lupi, including 4.7 micron IR-CO emission in our analysis. These IR-CO and UV-H2 observations were combined with 10 micron silicate emission, the 890 micron dust continuum, and 1.3 mm CO observations from the literature to infer a gapped structure in the inner disk. This single system has served as a testing ground for the larger Lupus complex sample, which we compare here to examine any trends between the outer disk morphology and inner disk gas distributions.

## Investigating Multiple Stellar Populations and Rotation in intermediate-age LMC star clusters

The extended main sequance turn off (eMSTO) has been observed in many intermediate-age star clusters. It's origin is still debatable, it could be due to multiple stellar popuations (MSP) or stelar rotation or other factors.  We use a new approach to investigate the MSP scenario, as well as rotation in star clustes by means of integrated spectra. Our results are consistent with the results obtained from CMD studies. Our presentation will give details on each of the clusters studies and compare it with the CMD literature result.

## Estimation of Magnetic Reconnection Rates and its association with Flare and CME’s

Ashish, Patel

We estimate the magnetic reconnection rates for 50 flares with flare class in the range of B to X based on GOES classification of solar flares observed with Solar Dynamics Observatory (SDO) during a period of 2011 to 2012. Parameters of reconnection namely inflow velocities, outflow velocities and the magnetic reconnection rates have been estimated. In order to calculate the inflow velocities, we analyzed flux measurements from HMI instrument onboard SDO which enables us to derive the dimensional reconnection rate. The outflow velocities are estimated using CME data which is available on the SOHO LASCO CME Catalogue (https://cdaw.gsfc.nasa.gov/CME_list/). Further, the ratio of the inflow and outflow velocities enables us to estimate the non-dimensional magnetic reconnection rate. We obtain the reconnection rates of the order of 10-2  to 10-4 from our observations. We have also attempted to establish a relation between the magnetic reconnection rate and the intensity class (GOES) of the flares.

## Modelling Coronal Mass Ejections' propagation in the inner heliosphere: a case study using forecasting model EUHFORIA

Asvestari, Eleanna

Coronal Mass ejections (CME) are one of the principal contributors to space weather, and are potential hazard to human life and activity in space and on ground. They have thus been the focal point of forecasting models aiming to accurately predict their arrival time at target, as well as their magnetic field configuration, which in the case of Earth-directed CME determines their geoeffectiveness. EUHFORIA is a data-driven magnetohydrodynamic model tracing the evolution of CME and CME-driven shocks through realistic background solar wind conditions. Its advantage over other similar models is that it employs a magnetic flux rope concept to model Interplanetary CME (ICME). To assess this new aspect of EUHFORIA two case-studies of well observed CME are being analysed and the modelled results are being compared to observations. The selection criterion for the two cases is that the CME is encountered by at least two well-separated spacecraft and exhibits flux rope signatures at both. One of the selected CME was encounter by Venus Express and STEREO-A, which were radially aligned at the time of the CME passage. The secont CME analysed was encountered by MESSENGER and WIND, which were longitudinally separated by 30 degrees. The choice of candidates will allow us to comprehensively evaluate the accuracy and utility of the employed flux rope modelling approach, not only in terms of radial evolution of the CME but also in modelling different parts of the propagating structure.

## Optical properties of the black hole:shadow

Atamurotov, Farruh

The shape of the silhouette (shadow) can be used to test the corresponding theory of gravity for describing physical processes in the vicinity of a supermassive black hole. We have investigated how the size and apparent shape of the black hole is distorted due to the black hole’s parameters by analyzing unstable circular orbits, i.e.,. We adopted two observables, the radius Rs and the distortion parameter δs, characterizing the apparent shape; we found that the shape of the shadow is affected by the value of the rotation parameter and so on. The motion of photons around axially symmetric rotating black hole were considered with different parameters of the black hole.

## Tracing the gas, dust and ice evolution in planetary systems with SPICA

Audard, Marc

SPICA, an infrared space mission operating in the mid and far-infrared has recently been selected for further study in the frame of ESA’s M5 call. SPICA will carry SAFARI, an infrared spectrometer operating from 34 to 230 µm (R˜300-11000), POL, an imaging polarimeter at 100, 200, and 350 µm, and SMI that will provide imaging spectroscopy with R˜100 and full-band slit-fed spectroscopy at R˜100-2,000 from 17 to 36µm, and R˜28,000 from 12 to 18µm. The SPICA telescope will be cooled down to about 8K, effectively suppressing most of the satellite's infrared thermal background, which will allow us to reach down to very low fluxes. SPICA will provide spectroscopic capabilities at a high sensitivity of 2-15 x1e-20 W/m2 (5s/1hr), about two orders of magnitude deeper than Herschel. One of the core science topics addressed by SPICA is "Tracing the gas, dust and ice evolution in planetary systems”. We present this topic to demonstrate the capabilities of SPICA.

## Probing the gas fuelling and outflows in nearby AGN with ALMA

Audibert, Anelise

Feeding and feedback in active galactic nuclei (AGN) play a very important role to gain a proper understanding of galaxy formation and evolution. The interaction between activity mechanisms in the nucleus and their influence in the host galaxy are crucial for the feedback and gas fuelling of the black hole (BH). Winds and outflows produced by the AGN can eject or heat the gas, terminate the star formation and through the lack of fuel for accretion, quench the black hole activity. Recent discoveries of massive molecular outflows have been promoting the idea that winds may be major actors in sweeping the gas out of galaxies, in agreement with theoretical predictions of AGN-driven winds models. AGN are fuelled by accretion of material onto the SMBH and the gas component can form stars on its way to the central engine. By studying the molecular gas in galaxy disks we want to understand: (i) how the star formation and nuclear activity are fuelled and what are the timescales involved, since both process rely on a common cold gas supply, but in different timescales? (ii) what are the mechanisms driving gas from the disk towards the nucleus, removing its large angular momentum and forming large non-axisymmetric perturbations?Our goal is to probe these phenomena by probing the gas inside the central kpc in nearby AGN. This has recently been possible due to the unique ALMA spatial resolution and sensitivity. We present a study of the morphology and kinematics of the cold dense gas in a sample of 5 nearby Seyfert/LINER nuclei at the unprecedented spatial resolution of 0.06-0.09” (3-10 pc), part of a new ALMA follow-up of the NUGA (NUclei of GAlaxies) program. NUGA is a high-resolution (0.5-1”) CO survey of 25 low luminosity AGN performed with the IRAM PdBI that has revealed smoking gun evidence of gas funnelling into the nucleus in 1/3rd of the sample, suggesting that galaxies may be alternating periods of fuelling and starvation.

## Ecliptic-poles Stellar Survey (EclipSS)

Ayres, Thomas

The Ecliptic-poles Stellar Survey (EclipSS) currently is collecting far-ultraviolet spectra (115-143 nm), with HST's ultra-sensitive Cosmic Origins Spectrograph (COS), of a sample of 49 F2-K2 dwarf stars in the North and South ecliptic polar regions, to further advance studies of magnetic activity among cool Main sequence stars similar to the Sun. The ecliptic poles are favored places for several current and up-coming astronomical survey satellites, including Gaia (astrometry), TESS (exoplanets and asteroseismology), and eROSITA (coronal X-rays). These instruments scan along lines of ecliptic longitude, and thus accumulate their deepest exposures close to the ecliptic poles.  The EclipSS targets were selected to be bright enough for eROSITA, not too bright for TESS, and just right for COS.  The combined photometric (starspots), asteroseismic, FUV, and X-ray measurements will provide wholistic information concerning rotation periods, sizes, masses, metallicities, ages, activity levels, and coronal properties to inform community-wide efforts to explore stellar activity and its underlying magnetic engine, the Dynamo.

## Searching for extended circumgalactic halos around galaxies

Azanha, Luiz

A full understanding of the galactic halo physical properties is an important missing piece in the picture of galaxy formation and evolution. The circumgalactic halo of a galaxy is important given that it may represent the reservoir of gas for future star formation. Radio observations of spiral galaxies using the 21cm-line of hydrogen show that galaxies have typically extended disks of neutral hydrogen which show a sharp edge. Beyond this point the galaxy may be dominated by ionized gas. This ionization may be caused either by the ultraviolet radiation from the galaxy itself or by ultraviolet background radiation. Detecting a hydrogen ionized halo gives us information about the total baryonic mass in galaxies and also about galaxy evolution. This detection is also a valuable as an indirect probe of the UVB radiation, which carries information about the cumulative history of star formation and AGN activity. This project is part of S-PLUS, a photometric survey of the southern hemisphere, which uses 12 bands, 5 SDSS broad and 7 narrow bands, designed to study stars and nearby galaxies. One of the filters covers Ha, which is the emission line related to recombination in ionized hydrogen. We will stack images of nearby galaxies using this sample, separating by morphology and stellar masses. A careful continuum subtraction will be necessary, using one or more broad band images. We expect to detect Ha emission from the halo, which is a direct detection of an ionized hydrogen gas. We will present our partial results.

## Gaia DR1 Evidence of Disrupting the Perseus Arm

Baba, Junichi

We have discovered a clear sign of the disruption phase of the Perseus arm in the Milky Way using Cepheid variables, taking advantage of the accurately measured distances of Cepheids and the proper motions from Gaia Data Release 1. Both the Galactocentric radial and rotation velocities of 77 Cepheids within 1.5 kpc of the Perseus arm are correlated with their distances from the locus of the Perseus arm, as the trailing side is rotating faster and moving inward compared to the leading side. We also found a negative vertex deviation for the Cepheids on the trailing side, -27°.6, in contrast to the positive vertex deviation in the solar neighborhood. This is, to our knowledge, the first direct evidence that the vertex deviation around the Perseus arm is affected by the spiral arm. We compared these observational trends with our N-body/hydrodynamics simulations based on a static density- wave spiral scenario and with those based on a transient dynamic spiral scenario. Although our comparisons are limited to qualitative trends, they strongly favor the conclusion that the Perseus arm is in the disruption phase of a transient arm.

## AGN torus properties investigated by the 4.7 micron CO absorption band

Baba, Shunsuke

In the active galactic nucleus (AGN) unified scheme, the central engine is supposed to be surrounded by a toroidal dusty material, so-called AGN torus, which is responsible for the obscuration of the radiation from the nucleus. The unified scheme of AGNs requires verification of the existence of AGN torus and investigation of its nature possibly linked with the surrounding environment. However, the small physical scale of the torus prevents us from direct spatially-resolved observations of it applicable for a large sample of AGNs. Instead, spectroscopy of near-infrared absorption lines can, with thermal radiation from a compact region heated by the nucleus as the background continuum, effectively resolve the foreground material and examine its physical states. On the basis of this approach, we observed the 4.7 micron CO absorption band (v=1<-0, DeltaJ=+/-1) in nearby (z<0.07) 47 infrared galaxies with the AKARI satellite. Many of the sample galaxies showed large column densities (N_H~10^23 cm-2) and high temperatures (several x 100 K) through the CO band profile. Such a large column of warm gas is difficult to be attained via UV and shock heating and probably heated by X-ray from an AGN. The distribution of the gas column density against the 14-micron luminosity used as an indicator of the AGN luminosity was qualitatively consistent with the obscured fraction determined in X-ray observations. This consistency supports the assumption that the CO absorption likely probes the region dominated by X-ray. We also found that AGN-starburst composites showed on average larger column densities than Seyfert 2s. This result suggests that the obscuration by an AGN torus is also effective in a composite and that the torus is geometrically thicker than that in a typical Seyfert. This difference may reflect the AGN-starburst connection that supernovae in a circum-nuclear disk assist the formation of a thick torus.

## Seeking for magnetic fields in rotating disks/jets around young stars

Bacciotti, Francesca

We have started a project with ALMA for a combined study of rotation and magnetic properties in disks and jets around low mass young stars. _x005F The motivation is to test the models of magneto-centrifugal launch of jets along the magnetic field lines that thread the disk. This mechanism is relevant for star formation, as the associated magnetic braking of the disk allows the extration of angular momentum from teh system and the accretion of disk material onto the central star._x005F Our plan is to use the polarimetric capabilities of ALMA to determine the magnetic configuration _x005F in systems with rotating jets and disks. In these cases, in fact, we expect to find strong ordered magnetization in the first ten of AU from the source._x005F We have recently obtained ALMA Band 7 polarimetric data for the young systems DG Tau and CW Tau, two T Tauri stars for which the rotation properties of jet and disk are well known. _x005F The analysis of these data reveals, however, that dust self-scattering concurs strongly with the magnetic configuration to the determination of the polarization patterns._x005F We present here the first results of the project, illustrating the different interpretations. Even in the case in which magnetic alignement is weak, the polarization configuration can be a powerful tool for the diagnostics of the dust properties in disks.

## A conception of proto-sun disk with high angular momentum evolution

Bagrov, Alexander V.

The Standard Planetary Cosmogony describes the evolution of protoplanetary nebula that remained near the young Sun. Its specific angular momentum j must be less than rotation stability limit for a single star with mass M¤: j ≤ 1.7·1017(M/M¤)2/3 cm2·s-1. On the other hand, minimal angular momentum required for the creation of a double star is 10 times more. When the specific angular momentum of the protostellar nebula is slightly less than j ≤ 1.7·1018(M/M¤)2/3 cm2·s-1, rotation of the nebula will stop its accretion to the center before the gathered mass will be enough to become a star. In this case, the protostellar nebula turns into a flat rotating disc. Dust particles in the disc will play a role of an effective refrigerator, so all material of the disc has to be cold. Gases in the disc will stop turbulence, so all particles will be on circular Keplerian orbits. All particles will have nearly exact Keplerian velocities with negligible differences produced by temperature. This will lead to a diffusion shift of low-speed particles to the center of the protostellar disc. So the mass of the central part of the disc will be steadily increasing without acquiring angular momentum. Eventually, the concentrated mass will be enough for producing a star, and the opacity of the central gaseous globe will lead to the heating of its inner part, which is necessary for the nuclear synthesis. Hence a star in the center of a fast rotating disk will have long rotation period.

## Interstellar striders as migrating bodies through planetary systems

Bagrov, Alexander V.

In 2011 at least 10 “free-floating planets” with roughly the mass of Jupiter were detected with gravitational microlensing. October 19, 2017, using the Pan-STARRS1 telescope in Hawaii astronomers discovered a small “interstellar strider” named ‘Oumuamua that crossed our Solar system luckily near to the Earth to be detected by survey telescope. Taking in account sensitivity of the telescope, visible velocity of the discovered object and a volume of space, where it was detected, the researchers supposed that such an interstellar body can penetrate into an inner part of the Solar system each year._x005F There are many reasons to believe that in the interstellar space may exist bodies much larger than ‘Oumuamua, though they will occur rarer. This assumption automatically will lead to a simple idea, that some of the interstellar striders can collide with bodies of our planetary system. If interstellar striders are “primordial” planetezimales lost by extrasolar planetary systems, they are ordinary comet nuclei that consist of frozen volatiles and dust. When they hit, say, the Earth, they can produce large flat collision craters (“astroblems”). All volatiles from the hitter will totally evaporate, and dust particles from comet nucleus will be the same as the dust of Earth soil. So no footprints of interstellar origin of hazardous hitter will be preserved. If 10-km sized interstellar strides are 100 times less rare than 1-km ‘Oumuamua, the probability of their direct collision with the Earth will be about 1 event in 100000 years. It may be only coincidence, but the time between the appearance of huge astroblems on the Earth surface is about 100000 years too. Hence we may suppose that interstellar striders play their own role in the evolution of the Solar planetary system.

## Outlying H-alpha blobs in SDSS IV MaNGA

Bait, Omkar

We have discovered a population of 28 outlying H-alpha emitters which appear as unresolved blobs in the SDSS IV MaNGA integral field unit (IFU) survey. These could be candidate dwarf galaxies with high specific star formation rates (sSFRs). We have used the recently released stellar population and ionized gas emission maps, derived using the Pipe3D pipeline, to visually identify H alpha emitting regions with no underlying optical continuum emission in deep imaging from the DECam Legacy Survey or Beijing-Arizona Sky Survey. Moreover, these H-alpha blobs have velocities which are different from the velocity map of the host galaxies. Starting from a sample of $\sim 2700$ MaNGA galaxies in the  Data Release 14, we identify 28 outlying H-alpha emitting blobs. We make apertures around these blobs and calculate the total fluxes around various emission lines to study their location on the Baldwin Philip and Terlevich (BPT) diagram, which shows that all of them are photoionised due to star formation. We also estimate their total star formation rates (SFR) and metallicities using the integrated emission lines.  We use the non-detections in the optical continuum as an upper limit on the absolute magnitude in the B band ($M_B$) of these candidate dwarf galaxies and compare them with the well known $M_B$-SFR and $M_B$-metallicity relations. We found that these galaxies have very high sSFRs compared to the local volume dwarfs. Some of the dwarf galaxies could belong to the faint end of the blue compact dwarfs (BCDs), blue diffuse dwarfs (BDDs), or tidal dwarf galaxy (TDGs) populations. However, the metallicites of these dwarfs galaxies shows that they are either consistent with or have lower metallicities than the standard $M_B-metallicity$ relation. Hence, we can at least rule out the possibility of them being TDGs.

## On the interdependence of galaxy morphology, star formation, and environment in massive galaxies in the nearby Universe

Bait, Omkar

Using multi-wavelength data, from UV-optical-near-mid IR, for $\sim$6000 galaxies in the local Universe, we study the dependence of star formation on the morphological T-types for massive galaxies ($\log M_*/M_\odot \geq 10$). We find that, early-type spirals (Sa-Sbc) and S0s predominate in the green valley, which is a transition zone between the star forming and quenched regions. Within the early-type spirals, as we move from Sa to Sbc spirals the fraction of green valley and quenched galaxies decreases, indicating the important role of the bulge in the quenching of galaxies. The fraction of early-type spirals decreases as we enter the green valley from the blue cloud, which coincides with the increase in the fraction of S0s. This points towards the morphological transformation of early-type spiral galaxies into S0s which can happen due to environmental effects such as ram-pressure stripping, galaxy harassment, or tidal interactions. We also find a second population of S0s which are actively star-forming and are present in all environments. Since morphological T-type, specific star formation rate (sSFR), and environmental density are all correlated with each other, we compute the partial correlation coefficient for each pair of parameters while keeping the third parameter as a control variable. We find that morphology most strongly correlates with sSFR, independent of the environment, while the other two correlations (morphology-density and sSFR-environment) are weaker. Thus, we conclude that, for massive galaxies in the local Universe, the physical processes that shape their morphology are also the ones that determine their star-forming state.

## Extended H-alpha emitters in the outskirts of galaxies in SDSS IV MaNGA

Bait, Omkar

We have discovered a sample of 13 extended H-alpha emitters (xHAEs) which lie away from the optical disc of host galaxy in the SDSS IV MaNGA integral field unit (IFU) survey. We have used the recently released stellar population and ionized gas emission maps, derived using the Pipe3D pipeline, to visually identify H-alpha emitting regions away from the host galaxy and having no underlying optical continuum emission in deep imaging from the DECam Legacy Survey or Beijing-Arizona Sky Survey. Starting from a sample of $\sim 2700$ MaNGA galaxies in the SDSS Data Release 14, we identify 13 outlying xHAEs. We make apertures around these xHAEs and calculate the total fluxes around various emission lines to study their location on the Baldwin Philip and Terlevich (BPT) diagram, which shows that they are photoionised due to an active galactic nuclei (AGN) or a mixture of both an AGN and star formation. We argue that these xHAEs are Hanny's Voorwerp like objects. In particular, we argue that they are fainter counterparts of the Voorwerp, since unlike the Hanny's Voorwerp which have such strong emission line flux that they were discovered in the broad band continuum imaging, our xHAEs do not have any bright optical counterpart.

## The reconfinement of AGN jets

Bamford, Thomas

The relativistic jets associated with active galactic nuclei (AGN) are capable of propagation over multiple length scales, extending up to a few billion initial jet radii. This remarkable stability can be understood in terms of the interaction of the jet with its surrounding environment. In particular, jet expansion associated with a decreasing external pressure can lead to causal disconnectivity across the jet, suppressing global instabilities. In at least some AGN jets, the external pressure eventually drives a reconfinement shock into the jet axis establishing causality across the jet once more. Past this reconfinement point the jet is therefore subject to global instabilities and will eventually become fully disrupted and turbulent. In 1997 Komissarov and Falle proposed a semi-analytic model predicting the position of the reconfinement point. This model is explored in more detail for different atmospheres. Strong deviations are found for steeply declining power law atmospheres, with the model significantly underestimating the reconfinement scale.

## A comparison of planetary embryos collision outcome in binary and single star systems : perfect merging versus a more realistic model.

Bancelin, David

By now, observations of exoplanets have found nearly 90 binary star systems hosting 125 planets. We expect these numbers to increase as 50 – 70 % of the main sequence stars in the solar neighbourhood are members of binary or multiple systems. The planetary motion in binary star systems depends strongly on both the parameters of the stellar system (i.e. stellar separation and eccentricity) and the architecture of the planetary system (i.e. number of planets and their orbital behaviour). In case a terrestrial planet moves in the so-called habitable zone (HZ) of its host star, the habitability of such a planet depends on further requirements among which the amount of liquid water on its surface is certainly a crucial factor.Models of planetary formation either in single or binary star systems favour a merging approach to estimate the outcome of collisions occurring between Moon-to-Mars-sized embryos during the early stage of planetary formation. As a consequence, the size and water content of the body resulting from a collision are systematically overestimated because of the assumption of perfect merging.In our study, we simulate collisions of same-sized embryos (either Moon or Mars size) initially placed in the region between 0.9 and 1.1 au which are perturbed by a giant planet of Jupiter mass and a secondary star. In these simulations, we derive statistics for the impact velocities and angles. Our results show that in comparison with a corresponding single star systems, the impact velocities are significantly higher in binary star systems in case the giant planet and the secondary star induce a secular resonance in the studied area.Combining our results with more realistic collisions simulations using a GPU 3D-SPH (Smooth-Particles Hydrodynamics) code, we find for both single and binary regimes, a significant loss of water and material especially at low impact velocities when the impact angle is less than 45°.

## SEARCH FOR EXOPLANETS AROUND NORTHERN CIRCUMPOLAR STARS: HD 18438 and HD 158996

Bang, Tae-Yang

We have conducted Search for Exoplanet around Northern circumpolar Stars (SENS program since 2010 over seven years using the high-resolution Bohyunsan Observatory Echelle Spectrograph (BOES) at the 1.8m telescope of Bohyunsan Optical Astronomy Observatory in Korea. We have accumulating precise radial velocity (RV) measurements for 224 target stars, and so far found seven exoplanets and more potential exoplanet candidates. As exemplary cases, we report the analyses on HD 18438 and HD 15899. Both show long-period RV variations, 719 days for HD 18438 and 820.2 days for HD 158996. We checked the chromospheric activities using Ca ii H and H_ lines, HIPPARCOS photometry and line bisectors to identify the origin of the observed RV variations. In the case of HD 18438, we conclude that the observed RV variations with period 719.0 days are likely to be caused by the pulsations because the periods of HIPPARCOS photometric and H_ EW variations for HD 18438 are similar to that of RV variations in Lomb-Scargle periodogram, and there are no correlations between bisectors and RV measurements. In the case of HD 158996, on the other hand, we did not find any similarity in the respective periodograms nor any correlation between RV variations and line bisector variations. In addition, the probability that the real rotational period can be as longer than the RV period for HD 158996 is only about 4.3%. Thus we conclude that observed RV variations with a period of 820.2 days of HD 158996 are caused by a planetary companion, which has the minimum mass of 14.0 MJup, the semi-major axis of 2.1 AU, and eccentricity of 0.13 assuming the stellar mass of 1.8 MSun. HD 158996 is so far one of the brightest and largest stars to harbor an exoplanet candidate.*  BTY is supported by BK21 Plus of National Research Foundation of Korea.

## Intermediate-Mass Black Hole Feedback in Dwarf Galaxies: a View from Cosmological Simulations

Barai, Paramita

Black holes are usually observed to be of stellar-mass or supermassive. By natural extension, there should be a population of Intermediate-Mass Black Holes (IMBHs: with mass between 100 to 106 Msun) in the Universe; which has started to been observed. An exciting claim has been made recently by Silk, J.(2017, ApJ, 839, L13): that there can be IMBHs at the centers of essentially all old Dwarf Galaxies. Early feedback by IMBHs in gas-rich dwarf galaxies at z = 5 - 8, can potentially solve multiple dwarf galaxy problems (e.g. core-cusp, number) within the Lambda-cold-dark-matter cosmology.We are performing Cosmological Hydrodynamical Simulations to test the case for IMBHs in Dwarf Galaxies. Our simulations employ the 3D TreePM SPH code GADGET-3, and include metal cooling, star formation, chemical enrichment, supernova feedback, AGN accretion and feedback (Barai, P. et al. 2016, MNRAS, 461, 1548). We are simulating small (2 Mpc)3 cosmological volumes with periodic boundary conditions, starting from z = 100. Black Holes of mass 1000 Msun are seeded inside halos when they reach a mass of 107 Msun. The black holes grow by accretion of gas from their surroundings and by merger with other black holes, and consequently eject feedback energy. We analyze the simulation output in post-processing to study the growth of the first IMBHs. We quantify the impact of IMBHs on their host Dwarf Galaxies; especially the effects on star formation in terms of negative or positive feedback.Our conclusions, based on numerical simulation results, support the phenomenological ideas made by Silk(2017). IMBHs at the centers of dwarf galaxies can be a strong source of feedback to quench star-formation and generate outflows. At the same time, these IMBHs form the missing link between stellar-mass and supermassive BHs.

## Particle Acceleration, Turbulence and Multi-Wavelength Radiation in Blazar Jets

Baring, Matthew

Jets in blazars are an excellent forum for studying acceleration at relativistic MHD shocks, since this process is likely to spawn the highly-variable emission seen across the electromagnetic spectrum from radio to gamma-rays. Our recent work on combining multi-wavelength leptonic emission models with complete simulated distributions from shock acceleration theory has resulted in new insights into plasma conditions in blazar jets, likely to apply to radio galaxies as well. This has demonstrated the ability to infer the plasma density, and suggested the interpretation that turbulence levels decline with remoteness from jet shocks, with a significant role for non-gyroresonant diffusion. In this paper, we extend this program to a two-zone time-evolving construction, modeling together both extended, enhanced emission states from larger radiative regions, and prompt flare events in select Fermi-LAT and TeV blazars. A prime goal is to ascertain whether such flares are truly associated with prompt shock acceleration activity in relatively confined regions. The results illustrate how parametric degeneracies in shock acceleration conditions can lead to refined determinations of the plasma density and particle diffusion character in blazar jets.

## Discovery of two new hot Jupiters: WASP-163 b and WASP-170 b

Barkaoui, Khalid

We present two new hot Jupiters, WASP-163 b and WASP-170 b, discovered by the WASP-South survey [Pollacco et al. 2006]. We performed a combined analysis of radial velocity data obtained with the CORALIE spectrograph mounted on the 1.2 m Euler-Swiss telescope [D. Queloz et al. 2001] and follow-up transit observations with the TRAPPIST-North [M. Gillon et al. 2017], TRAPPIST-South [M. Gillet et al. 2011; E. Jehin et al. 2011], NITES [McCormac et al. 2014] and Euler telescopes, to determinate the system parameters (K. Barkaoui et al. in prep). WASP-163 b and WASP-170 b are slightly larger than Jupiter while being about twice more massive, and are in short orbits (<3 days) around bright (V<13) solar-type stars. The radii of WASP-163b and WASP-170b are well reproduced by classical models of irradiated giant planets [J. J. Fortney et al. 2017]. This discovery made use of a new 60 cm robotic telescope, TRAPPIST-North, installed in spring 2016 at Oukaimeden Observatory in Morocco. It is an instrumental project led by the University of Liege (Belgium), in collaboration with the Cadi Ayyad University of Marrakech (Morocco), that is, like its southern twin TRAPPIST-South, totally dedicated to the observations of exoplanet transits and small bodies of the solar system.

## MHD turbulence, self-gravity and radiative cooling effects on star formation regions

Barreto M. dos Santos, Lucas

In spite of being the focus of intense investigation for several decades, the comprehension on how star formation (SF) occurs is still a great challenge. In our galaxy, it is well known that stars are formed in dense regions within giant molecular clouds. The total internal pressure (thermal plus magnetic) in the clouds is, in general, large enough to prevent its gravitational collapse and an external agent, like turbulence driven by supernova shocks, spiral waves or stellar winds may be necessary to provoke the formation of high density, supersonic regions that may in turn collapse to form stars or an entire group of them. In this work we present three-dimensional MHD simulations of star formation regions considering the effects of radiative cooling and self-gravity in the overall process of ISM turbulence evolution and clouds collapse. Several models involving different regimes of super to sub-Alfvenic turbulence have been considered. In general lines, the results reveal the formation of elongated filaments with a few star-forming cores mainly at the confluence of the filaments, resembling, e.g., the recently observed features of the ISM by Hershel and CCAT at mm wavelengths. A detailed statistical analysis aiming at the characterization of several observable quantities, like the probability density function (PDF), the core mass function (CMF), the density power spectrum, and the overall magnetic field orientation in the filaments as a function of their size and scales will be also presented. In particular, we find that at large scale, more diffuse regions, the overall magnetic field orientation is parallel to the filaments while at smaller, denser regions, where self-gravity confinement prevails, the magnetic fields are in general perpendicular to the filaments, in consistency with observations. Finally, we will present direct comparisons of the simulations with selected regions of Hershel, CCAT and PLANCK foreground.

## Direct Calibration of Gaia Photometry for White Dwarf Stars on the HST Flux Scale

Barstow, Martin

Gaia photometry is calibrated with respect to a large ensemble of stars of many differing spectral types. We have used a large sample of pure hydrogen DA white dwarfs, with well-defined temperatures and gravities, to compute synthetic photometry for these stars using the Gaia DR2 band passes. By comparing observed  and synthetic Gaia G, BP and RP photometry it is possible to define zero points and magnitude off sets that link Gaia magnitudes with the HST photometric scale.

## PROPERTIES OF HEAVY TRANSURANIUM ELEMENTS BY R-PROCESS NUCLEOSYNTHESIS DURING EXPLOSION OF SUPERNOVA TYPE II : A THEORETICAL PERSPECTIVE

BARUAH, RULEE

Nuclear astrophysics has come up as a very important topic in recent times due to the report of many new super heavy and ultra heavy elements formed in laboratories. Here we discuss a model for production of heavy elements along the rapid neutron capture (r-process) path during explosion of supernova type II. For most of the heavy and superheavy elements produced here, the experimental information is largely scarce. So a theoretical approach is considered essential for gathering information on the nuclei produced in such environments. _x005F Stars in the mass range 10-30 M⊙ evolve to form iron cores of 1.3 to 1.6 M⊙. These iron cores collapse according to well known instabilities, photodisintegration and electron capture. During collapse an outward bound shock wave forms in the matter falling onto the nearly stationary core. The conditions behind the shock at 100 to 200 km are suitable for neutrino heating . This neutrino heating blows a hot bubble above the protoneutron star and is the most important source of energy for Supernova Explosion. The most interesting evolution occurs as temperature falls from 1010 K to 109 K. Another astrophysical parameter needed for our analysis is neutron number density which we take to be greater than 1020 cm-3 . Along the path , the experimental data of observed elements matches our calculated one . It produced heavy neutron-rich nuclei with A > 240. Unlike high densities, at low density of 1020 cm-3 and T9 = 2.0 , the path contains all the elements as observed. Heavy transuranium elements (Z = 93-95) and their beta decay rates are obtained at densities >1020 cm-3 and are found to be in agreement with the experimental values of Audi et al (2003). It is found that the beta decay rates are much higher than the corresponding electron capture rates at the same classical condition. the_x005F Key words : R-process, nucleosysthesis, supernova, beta decay

## OBSERVATION OF SOLAR ACTIVE REGION 12403

Batmunkh, Batbayar

In some works it was shown that, sudden disappearances of filaments have correlations with the phenomenon of coronal mass ejections. Also, some filament generates a low-power flare. Thus, it can be seen from many studies that filament plays an important role in the mechanism of occurrence of flares of some types. In this paper H-alpha observations of the solar active region (NOAA 12403), obtained at the coronograph of the astronomical observatory "Khurel togoot" of Mongolia, are presented. The filament in AO12403 after some time its appearance and length changed, that is, the intensity or its brightness decreased, and more accurately, some part of this filament became almost invisible. After that almost in its place there was a flare, moreover, it was very stable, and its glow lasted for a long time intensive. It can be seen that in this case the eruption of the filament and the appearance of the flare have a direct relationship with each other and, possibly, a magnetic field has been restructured.

## On the formation of black holes in High-mass X-ray Binaries

Batta, Aldo

High-mass X-ray binaries (HMXRBs), such as Cygnus X-1, host some of the most rapidly spinning black holes (BHs) known to date. However, spin measurements from LIGO events produced by the mergers of binary black hole systems with masses ranging from 7 to 36 solar masses have low effective spins, consistent with low spin values. Assuming that the BH spin comes from the direct collapse of the star, we study the evolution of BH properties (mass and spin) as it accretes shells of infalling material from 1D stellar profiles with different rotation. When feedback from the formation of an accretion disk around the BH is included, the integrated feedback is large enough to unbind the collapsing star. If this energy is efficiently deposited into the infalling layers the collapse of the star will be halted, yielding BHs less massive and with a smaller spin that the one expected from the entire collapse of the star.

## Magnetic fields at the epoch of reionization

Battaner, Eduardo

We detected magnetic fields with strengths of the order of 10-8 G at the epoch of Reionization. These were identified by using CMB data to obtain Faraday Rotation at both, the map and the spectrum level. The multipole region of about l<12 and the lack of correlations with either, galactic emissions (Faraday rotation, synchrotron and dust) or with CMB anisotropies and lensing, support our identification.

## A THEORY AND SIMULATION-BASED CONVECTIVE BOUNDARY MIXING MODEL FOR AGB STAR EVOLUTION AND NUCLEOSYNTHESIS

Battino, Umberto

The s-process nucleosynthesis in Asymptotic Giant Branch (AGB) stars depends on the modelling of convective boundaries. I present models and s-process simulations that adopt a treatment of convective boundaries based on the results of hydrodynamic simulations and on the theory of mixing due to gravity waves in the vicinity of convective boundaries, where Hydrodynamics simulations suggest the presence of Convective Boundary Mixing (CBM). In this work I apply a CBM model purely motivated by simulations and theory, with no finetuning by hand "a priori" to match observations, to 1D stellar evolution models with initial mass M = 2 and M = 3 solar masses , and with initial metal content around the solar value. This mixing is affecting the Ne22(gamma,n)Mg25 activation and the s-process efficiency in the C13-pocket. The theoretical results are in good agreement with observations: at the end of the AGB evolution, we obtain an s-process production 0.36<[s/Fe]<0.78 and -0.23<[hs/ls]<0.45, which is consistent with spectroscopic observations of C-rich AGB stars.

## A Coordinated Approach for Planetary Science with Astrophysics Assets

Bauer, James

Planetary Science has benefited greatly from observational platforms whose highest priorities have not originally emcompassed the studies of bodies within our solar system. The first measurements of X-rays from giant planet aurorae and comets, the discovery of comet and asteroid dust trails, and the largest surveys of asteroid and comet diameters were the results of observations using assets originally intended for astrophysical studies. The great observatories: Hubble Space Telescope, Spitzer Space Telescope, and Chandra X-ray observatory, have done a comprehensive array of planetary science investigations, as well as other smaller missions (e.g. WISE, Kepler, SWIFT, etc).  Additionally, future assets, such as JWST and LSST, will make further rich contributions and are considering moving target observations in their planning and operational phases. Findings by NASA planetary assessment groups in 2017 encouraged the further use of astrophysics assets by planetary scientists, and the formation and definition of the necessary capabilities for these platforms to support planetary science. To that end, the NASA Planetary Science Division has constituted a group to investigate and receive input as to the desired functionalities of future astrophysics assets, with the long-term idea of providing a list of these faculties to inform future missions during the early technical design phases. We will present the progress and preliminary findings from the activities of this group in its efforts to compile a uniform set of basic capabilities and to maximize the yield of Solar System science with future Astrophysics assets.

## Refueled and shielded - the early evolution of Tidal Dwarf Galaxies

Baumschlager, Bernhard

We present, for the first time, numerical high-resolution simulations of young tidal dwarf galaxies (TDGs), including a self-consistent treatment of the tidal arm in which they are embedded. Thereby, we do not rely on idealised initial conditions, as the initial data of the presented simulation stem from a galaxy interaction simulation. We compare these embedded models with those ones ususally applied but isolated from the tidal arm. Here we demonstrate the importance of the tidal-arm gas reservoir on the evolution of TDGs as gas can be accreted and is available for subsequent conversion into stars. During the initial collapse of the initially Jeans unstable proto-TDG, with a duration of a few 100 Myr, the evolutions of the embedded and isolated TDGs are indistinguishable. Significant differences appear however after the collapse has halted and the further evolution is dominated by the ongoing accretion of material from the surroundings of the TDGs. The inclusion of the tidal arm in the simulation of TDGs results in roughly a doubling of the gas mass and gas fraction, an increase in stellar mass by a factor of 1.5 and a ~5 times higher star formation rate (SFR) compared to the isolated case.Such high SFR leads to compact young blue star-dominated dwarf galaxies (DGs) which will survive supernova feedback and lateron either dissolve from the mature galaxy as ilolated dwarf ellipticals or when keep bound probably develop to the type of faint compact DGs found as satellites around massive cluster galaxies.

## Dynamical Effects of Detected Giant Planets on the Habitable Zone in Binary Star Systems

Bazso, Akos

We present a survey of binary star systems with detected circumstellar extrasolar planets. The sample includes stars with separations up to 500 au. The presence of a Jupiter-like giant planet gives rise to a variety of gravitational interactions. Such interactions include mean-motion resonances (MMR) as well as secular resonances (SR). Secular resonances often entail highly eccentric motion. We use a semi-analytical method to find the locations of SRs, which are basically determined by the orbital precession frequencies of the massive bodies. For the systems at hand we investigate three possible orbital configurations of the giant planet: it is located either (1) exterior to the habitable zone (HZ) like in the solar system, (2) interior to the HZ like in case of Hot Jupiters, or (3) right inside the HZ. From the perspective of additional habitable terrestrial planets the last configuration is unpleasant. For the first configuration we demonstrate that there is always an SR interior to the giant planet's orbit. Under certain circumstances – depending on the system's architecture – this SR might fall into the HZ and cause highly eccentric motion of terrestrial planets. If additional MMRs are active this could even lead to the ejection of the terrestrial planet from the system. The second configuration is more safe in terms of SR, but including general relativistic perturbations SRs are possible, too. Generally, giant planets exterior to the HZ are less favourable in binary star systems. The majority of planets in our sample belongs to the second configuration, though, so we predict a fair chance to observe additional terrestrial planets in the HZ.

## Binary Star Systems with Circumstellar Habitable Zones Affected by Resonances

Bazso, Akos

Extrasolar planets have been detected in a vast diversity of orbital configurations. Among them, wide separation binary star systems with circumstellar extrasolar giant planets have been shown to successfully form terrestrial planets in the host star's habitable zone (HZ). We focus on binary star systems with stellar separations from 20 AU up to several hundreds of AU. In this study we demonstrate that under suitable circumstances secular resonances (SR) might fall into the HZ and cause highly eccentric motion of terrestrial planets. We analyse the circumstances for which an SR is present in the HZ, and show the dependence on various system orbital and physical parameters. By applying a combination of simple analytical models we determine the orbital precession frequency of the giant planet and relate it to the corresponding frequencies of test planets in the HZ. We focus on the spectral type of the host star for different HZ ranges, and treat the orbital distance and eccentricity of the secondary star (which are often poorly constrained from observations) as free parameters. Our study shows that for any given location of the giant planet there exist configurations in which an SR appears somewhere in the HZ. Even for relatively distant secondary stars the giant planet's precession frequency might push terrestrial planets in the HZ to become eccentric. In summary, in wide binary systems with a giant planet exterior to the HZ, secular perturbations can affect the HZ. These perturbations drive terrestrial planets to more eccentric orbits, which increases the insolation received by the planet and could lead to uninhabitable conditions on the planet.

## Curating Space Museums via Intersectional Design

Bazzi, Wael

My research examines the reinvention of the modern space museum not as an accommodation of historical artefacts, but as a platform for intersecting creative, entrepreneurial, educational and cultural innovations and influences of the space sector under one roof. Thus, the focus of the space museum shifts towards highlighting the greater good afforded to society (and humanity) by the space complex’s capacity for embracing and shaping the future, as opposed to nostalgically ruminating the past. To successfully achieve this, the proposed museum would need to undergo bi-annual turnover or up-cycling of its exhibits to match recent discoveries made in the space science community, as well as mediums of dissemination such as VR. To curate meaningful content for such a museum requires the close collaboration of multidisciplinary scientists and humanists with an intimate understanding of developments in cosmological, physical and aerospace science, as well as current affairs. In designing such exhibits, a team of creative technologists capable of suggesting avant-gard mediums of expression and experimentation would be rotated on the curation board alongside their fellow educators and scientists.By employing intersectional and trans-disciplinary design in their curation process, space museums benefit from a range of innovative and cost-effective advantages that outshine conventional models of public outreach and curation.I hypothesise that this method of curation will shift the dialogue about the role of Space Science in everyday public life, precisely by engaging head on with other cultural institutions, and may well lead to other previously unexplored collaborations. Through interactive art and sensory stimulation technology, the space museum offers a framework for putting space scientists in the front-seat of science communication, cultural engagement, and public outreach.

## Starburst Dwarfs: the Super Star Clusters Form at Filament Hubs

Beck, Sara

The ”starburst” in starburst dwarfs is usually in one or a few super star clusters. These young clusters include the most extreme star formation in the local Universe; they hold up to 106M? of stars younger than 5 Myr in a few pc3, and one such deeply embedded cluster can dominate the total luminosity of the galaxy. What triggers the starburst activity? In what environment do these clusters form? How do these intense concentrations of young OB stars interact with their embed- ding clouds? To answer these questions, we use ALMA, the SMA, the JVLAand TEXES (a high–resolution mid-infrared spectrometer) to observe molecules, ions and dust in nearby starburst dwarfs. Typical spatial and spectral resolution are ˜ 5 pc and ˜ 4 km/s . We find that the starforming clouds are hot and dusty, and appear as distinct filaments. In NGC 5253 the bright embedded cluster is accreting a massive filament, and in He 2-10 the young clusters have formed where several filaments meet in a ’hub’. In some galaxies we see ionized gas escaping from the embedded ionized nebulae in slow pressure-driven flows.

## New results on the magnetic field in M31

Beck, Rainer

The magnetic field of M31 is very regular, preserving its direction along a ring-like structure in the disk. This is regarded as the first and best evidence so far for the action of a large-scale dynamo in spiral galaxies. The regular field leads to fast diffusion of cosmic rays and prevents the formation of a radio halo of detectable surface brightness. The magnetic field in the central region is inclined to the disk and of opposite direction, indication of a major merger event in the past. New Effelsberg surveys at 11.1, 6.2, and 3.6 cm allowed us to derive maps of synchrotron emission, magnetic field strengths, and Faraday rotation with improved resolution and accuracy. M31 became the cornerstone to investigate the nonthermal properties of spiral galaxies.

## Seismic Probing of the first dredge-up event and tidal interactions in red-giant binaries

Beck, Paul

Binaries in spectroscopic systems provide a homogeneous set of stars. Differences between parameters, such as age or initial conditions, which otherwise would have strong impact on the stellar evolution and blur the comparison on a star-to-stars basis, can be neglected. In this poster, we present the comprehensive analysis of KIC9163796, constituted of two red giants of ~1.4±0.1Mo. The masses of the two components differ only by 1.5±0.5%. We show that both stars are located in the short-lived phase of the first dredge up on the red-giant branch, when the convective envelope reaches the deepest penetration into the star. While asteroseismology allows to characterise the primary component well, the large difference in lithium abundance between the two otherwise very similar components is used to test stellar evolutionary models. From a study of tidal interactions in the ensemble of red-giant binary systems, we conclude that the close resemblance of the surface rotation and orbital period is a coincidence and does not correspond to a sign of spin synchronisation. The comparison of the rotation period inferred from asteroseismology and surface rotation indicates that the convective envelope is rotating rigidly.Evidence for the detection of the power excess of the secondary component in the composite power spectrum is presented. Therefore, KIC9163796 is one of the prototypes of binary systems with two oscillating red-giant components. Such seismic systems, which offer many constraints, can be employed as benchmark object to be use to calibrate evolutionary models and stellar ages.Related papers:Beck, Kallinger, Pablovski, et al. 2018a, A&A 612, A22Beck, Mathis, Gallet, et al. 2018b, MNRAS, under revision

## Tracking the distribution of small dust grains through UV photometry

Beitia-Antero, Leire

Small (sizes < 0.5 microns) dust grains and large molecules, such as Polycyclic Aromatic Hydrocarbons, are very sensitive to short wavelengths. In particular, the ultraviolet (UV) range is of special importance because it contains the strongest feature of the extinction curve at short wavelengths: the 2175A bump or UV-bump. Studying the relative fraction of small to large dust grains allows to detect the regions on which dust coagulation is taking place or small dust grains are being destructed. We have combined GALEX NUV photometry with 2MASS infrared extinction maps to study the global distribution of small dust grains in the Orion Molecular Cloud as well as in the nearby, in projection, Rosette cloud. Evidence of variations in the strength of the UV bump has been found in the densest regions and also in heavily irradiated areas.

## Update to the Whole Heliosphere Interval (WHI) Solar Reference Spectrum

Béland, Stéphane

As part of the 2008 Whole Heliosphere Interval (WHI) efforts, a new Solar Irradiance Reference Spectra (SIRS,) near solar minimum, was determined from 0.1 nm to 2400 nm using a combination of satellite and sounding rocket observations. The WHI campaign covered the solar Carrington Rotation 2068 (20 March to 16 April 2008) and included a Quiet Sun period (10 - 16 April 2008).We are presenting an update to the SIRS using the latest version of the various data products used initially as well as a different time range for the Quiet Sun to reflect the observed period of Solar minimum.

## Omega Centauri: HST internal kinematics

Bellini, Andrea

We look at the internal kinematics of the multiple stellar populations of the globular cluster ? Centauri in an external Hubble Space Telescope (HST) field located at about 3.5 half-light radii from the center of the cluster. Thanks to the over 15-yr long baseline and the exquisite astrometric precision of the HST cameras, well-measured stars in our proper-motion catalog have errors as low as ~10 µas yr-1, and the catalog itself extends to near the hydrogen-burning limit of the cluster. We show that second-generation (2G) stars are significantly more radially anisotropic than first-generation (1G) stars. The latter are instead consistent with an isotropic velocity distribution. In addition, 1G stars have excess systemic rotation in the plane of the sky with respect to 2G stars. We show that the six populations below the main-sequence (MS) knee identified are associated with the five main population groups recently isolated on the upper MS in the core of cluster. Furthermore, we find both 1G and 2G stars in the field to be far from being in energy equipartition, with ? 1G=-0.007+/- 0.026 for the former and ? 2G=0.074+/- 0.029 for the latter, where ? is defined so that the velocity dispersion s µ scales with stellar mass as s µ proportional to m-? . The kinematical differences reported here can help constrain the formation mechanisms for the multiple stellar populations in ? Centauri and other globular clusters.

## Omega Centauri: Multiple Populations Galore

Bellini, Andrea

We take advantage of the exquisite quality of the Hubble Space Telescope to distill the main sequence of ? Cen into its constituent populations. To this end, we restrict ourselves to the five most useful filters: the magic “trio” of F275W, F336W, and F438W, along with F606W and F814W. We develop a strategy for identifying color systems where different populations stand out most distinctly, then we isolate those populations and examine them in other filters where their subpopulations also come to light. In this way, we have identified at least 15 subpopulations, each of which has a distinctive fiducial curve through our five-dimensional photometric space. We confirm the MSa to be split into two subcomponents, and find that both the bMS and the rMS are split into three subcomponents. Moreover, we have discovered two additional MS groups: the MSd (which has three subcomponents) shares similar properties with the bMS, and the MSe (which has four subcomponents) has properties more similar to those of the rMS. We examine the fiducial curves together and use synthetic spectra to infer relative heavy-element, light-element, and helium abundances for the populations. Our findings show that the stellar populations and star formation history of ? Cen are even more complex than inferred previously.

## Photometry of high-albedo outer main-belt asteroids

Belskaya, Irina

The parameters characterizing magnitude phase dependences of asteroids are found to be very similar for objects belonging to the same composition type. The discovered correlation  of the photometric parameters such as the amplitude of the opposition effect and phase slope on albedo gives an alternative way to estimate asteroid's albedo (Belskaya and Shevchenko, Icarus 197, 94, 2000). Thus, the measurement of magnitude-phase dependence of an asteroid can provide complimentary information on its albedo and composition type. We present new photometric observations of the selected asteroids from the outer part of asteroid belt. The asteroids were selected based on their high values of radiometric albedos given by the WISE and/or AKARI infrared surveys. Our aim is to compare their magnitude phase dependences with those from the inner part of asteroid belt and to provide an independent check of surface albedo and composition type of these asteroids. Knowledge of the fraction of high-albedo asteroids in the outer asteroid belt where majority of asteroids have low albedo surfaces is important for understanding the formation and evolution of our Solar system.

## The Arab Astronomical Society (ArAS): Developing Astrophysics Research in the Arab World

Benkhaldoun, Zouhair

The Arab Astronomical Society (ArAS) was officially created during the constitutional assembly held in Marrakech (Morocco) on November 30, 2016. ArAS is composed of a group of Arab researchers and students in the field of astrophysics who aim to develop research in this field in the Arab world (22 countries). ArAS is working on bridging the gap between the Arab astrophysicists in the Arab world and those around the world by organizing collaborative workshops, international scientific meetings, offering scholarships, and developing graduate programs in astrophysics. ArAS is working on establishing scientific infrastructure in the Arab world by training advanced undergraduate and graduate students in astrophysics and stimulating the built of new telescopes on the best sites in the Arab world. This will be accomplished through the hosting of specialized schools in astrophysics, facilitation of students' and postdocs training in international research centers and universities, the establishment of prizes in astronomy to honor leading Arab scientists in astronomy and to motivate young people to present distinctive works in astronomy.We present here the main goals of ArAS, its Strategic Plane at short, medium, and long term, as well as the organizational structures that will enable us to achieve our goals. We present methods and platforms to disseminate astronomy in the Arab World through the Arab Scientific Community Organization.  We give as well, some information we could gather about the situation of astrophysics research at the Arab countries in term of astrophysics institutions and astronomical observatories they hosted.

## Transiting Exoplanets and Their Atmospheres in the Era of James Webb Space Telescope: What We expected for the Systems like TRAPPIST-On/Seven Planets?

Benkhaldoun, Zouhair

Among the thousands of known exoplanets, the few of them that transit bright nearby stars have had the highest impact on our overall understanding of the large planetary population hosted within our galaxy. This is because their detailed characterization (mass, size, orbit, atmosphere, obliquity, etc.) can be measured with existing observational technology. The last decade saw the first observational constraints on the atmospheric properties of short-period planets transiting nearby stars, including the first firm detections of molecular signatures in exoplanetary atmospheres. These pioneering studies, performed with space and ground-based instruments, have provided initial glimpses at the atmospheric chemical and molecular composition, vertical pressure-temperature profiles, albedos, and circulation patterns of extrasolar worlds. The next major step is undoubtedly the upcoming launch of the James Webb Space Telescope (JWST), the Transiting Exoplanet Survey Satellite and CHaracterising ExOPlanet Satellite. These space-borne missions will offer an unprecedented capability to study of these nearby transiting exoplanets. JWST is particularly important, since it will provide large aperture, a heliocentric orbit, and continuous wavelength coverage from 0.6 to 28 microns. It should be powerful enough to make possible detailed atmospheric characterization not only of hot Jupiters but also of smaller planets. This sample will include more temperate terrestrial planets recently found orbiting in the habitable of nearby very-low-mass red dwarfs. The TRAPPIST-North Telescope Located at the Oukaimeden Observatory in Morocco contributed critical data to discovery of TRAPPIST exoplanetary system orbiting the TRAPPIST-1 red dwarf star. We propose to present a discussion about the scientific information we expected to gather from JWST data set in the observations of the Trappist-1 system in advance of   the congress that we intend to organize in Marrakech on this subject in 2020.

## Atlas Dark Sky Reserve: Towards the creation of the First Dark Sky Reserve in North Africa

Benkhaldoun, Zouhair

In 2016, Morocco organized the United Nations Climate Change Conference (COP22) in Marrakech. Following this conference, Morocco, like other countries, has made the commitment to become a major player in the fight against pollution. In this context, the Atlas Dark Sky project was born and today it becomes a reality and a project in progress.  In fact, the broad spectrum of impacts of light pollution is directly related to pollution and thus global warming. To cite only one example, taking measures against light pollution will reduce the energy bill of the countries and consequently reduce their contribution to the carbon emission.In this poster, we will present the Atlas Dark Reserve project, a project that aims to create the first Dark Sky reserve in North Africa and the biggest one in the world. The Observatory of Oukaïmeden located at the Atlas Chain in Morocco will be the central region of this reserve. Dark Sky Communities will be composed of about 120 villages and cities located in a diameter of 80 km from the central region. We will present our Strategic Plan (2018-2021) to create Atlas Dark Sky reserve in Morocco.

## MAPPINGS photoionization models of H II regions in dwarf irregular galaxies

Bensch, Katarzyna

Star-formation has a direct influence on chemical abundances of galaxies. Gas-rich dwarf irregular galaxies (DIGs) are less chemically evolved and therefore are great laboratories for detailed studies of chemical evolution. Their star-formation histories are simpler than those of massive galaxies. Especially isolated DIGs are important sources for understanding star-formation. They have been formed and evolve far from dense cluster centres and the gravitational influences of massive companions. The isolation allows us to study star-formation that originates purely from evolutionary processes of the pristine IGM in galaxy environments. We use Integral Field data to study 7 metal-poor DIGs with VLT/VIMOS and 13 isolated gas-rich DIGs from the SIGRID sample obtained with WiFeS. The H II emission suggests ongoing star-formation for the past 5 Myr. Metallicity estimates for HII regions of DIGs are one of the most important tools  towards an understanding of galaxy evolution since those studies require a precise metallicity calibration. We derive theoretical models using the MAPPINGS photoionization modelling code to predict theoretical emission line ratios at different values of metallicity and ionization parameters. The detection of multiple emission lines of H, O, N, Ne, He, S, and Fe allows us to use and compare different line-ratio grids to study the metallicity of the different HII regions. We investigate their resolved chemical composition, paying special attention to the metallicity-age connection. We discuss the problems arising from the limitations of simple geometric models and depletion of elements onto dust. The spatially resolved star formation history is consistent with the predictions from the models over the several hundred million years.

## ??Mean field dynamo in dwarf galaxies

Bera, Prasanta

Dwarf galaxies are generally faint but these are highly abundant in number count. Some of these galaxies (e.g. NGC 1569, IC 10, NGC 4449) show a strong large-scale magnetic field of strength about 10µG or more. The presence of an ordered strong magnetic field with similar strength in spiral galaxies is considered to be generated from the seed magnetic field by the dynamo action due to the differential rotation in the disk plane. On the other way, the strength of the differential rotation is small in a dwarf galaxy hence does not usually prefer large-scale dynamo. From the study of mean field dynamo in a thick disk, we find that the resistive dissipation is effectively less due to thicker vertical height. It can generally explain the strong ordered magnetic field in the dwarf galaxies.

## Following the trail of water from interstellar space to inhabited planets with the Origins Space Telescope

Bergin, Edwin

The Origins Space Telescope (OST) is one of four mission concepts that NASA is exploring in advance of the next decadal survey in the United States.   OST has tremendous relevance for tracing the origins of the stars, planets, and life from first light to present day.  In this talk I will describe the latest mission concept,  which will have a circular 5.9m aperture with a cryogenically-cooled telescope.  The instruments will cover wavelength ranges from 5 to 400+ microns and include both spectrographs and imagers.  In the mid-infrared, a purpose-built spectrometer will constrain the atmospheric composition and thermal structure of temperate Earth-size worlds via the transit technique with the goal of detecting two distinct biomarkers (methane and ozone), along with water and CO2.  This suite of molecules will determine whether the atmospheres of these potentially habitable worlds are in disequilibrium -- the signature of life.   With its tremendous spectral grasp and superb sensitivity, OST will survey water, both gas-phase and ice, toward as many as a thousand sources spanning all evolutionary stages of star and planet formation from molecular clouds to YSOs to planet-forming disks.  OST will possess the capability to measure the water's distribution in planet forming disks through observation hundreds of lines from the ground state lines that probe beyond waters iceline to higher energy transitions that emit only from interior to the snowline.  OST can also sample the water content via a combined study using a unique far-IR tracer of the highly uncertain disk gas mass, hydrogen deuteride.  I will also discuss how OST will transform our knowledge of the origin of Earth’s water by extending the sample of cometary bodies with detections of the D/H fingerprint by over an order of magnitude.

## LIGHT, WATER, LIFE: THE SEARCH FOR NEW WORLDS IN THE GALAXY. AN EDUCATIONAL PROJECT AT REGIONAL LEVEL IN ITALY

Bernagozzi, Andrea Ettore

Progetto Diderot, devised, proposed and realised by the Fondazione CRT of Turin (www.fondazionecrt.it), is one of the leading high-level educational initiatives in Italy. During the school year 2017-18, it included for the first time a project line devoted to astronomy, thanks to the collaboration with the Astronomical Observatory of the Autonomous Region Aosta Valley (www.oavda.it). The topic is one of the most intriguing fields in current science: the search for alien worlds and their comparison with the Solar System. This entails a multidisciplinary approach that exploits the fascination of cosmos to span fields as diverse as maths, physics, chemistry, Earth sciences, biology, as well as history, philosophy, literature and the arts.From November 2017 to April 2018, the activities of the project have reached more than 6.000 students in the Italian regions of Piedmont and Aosta Valley. The proposed activities are:Teaching Unit 1: “Let’s colour the planets”, for the primary school (age 6-10)Teaching Unit 2: “Let’s pack the suitcase for space”, for the middle school (age 11-13)Teaching Unit 3: “A thousand billion planets”, for the secondary school (age 14-18)An optional follow-up activity has also been proposed to middle and secondary schools; it asked the students to lay down a scientific report.The project required a sizeable logistic and educational effort in order to organise the activities held in hundreds of classes during 6 months, and to figure out the best strategies to pass down the scientific contents. Our presentation describes the project’s origin, how the contents have been devised, the methods developed to impart them, and the feedback got from the students. In the next school years, the project is expected to collect valuable information about the relationship between the school and research domains and to help us assess the impact that astronomy-based activities have on school curricula.

## The International Virtual Observatory Alliance

Bertocco, Sara

At the beginning of 2000s, astronomers had the dream to realize a Virtual Observatory, i.e. a system allowing scientists to access and analyze data coming from different astronomical instruments (telescopes, space missions and simulations) and archives as they are taken from a unique observatory. To achieve this result, it was needed to build a world wide infrastructure able to provide access to data coming from different instruments and stored in different archives, giving scientists the ability to discover, analyze and combine real and simulated data. This can be done making data and archives interoperable and accessible in a seamless way.The International Virtual Observatory Alliance (IVOA), formed in 2002, is the organization that debates and agrees the technical standards that are needed to make the VO possible. It also acts as a focus for VO aspirations, a framework for discussing and sharing VO ideas and technology, and body for promoting and publicizing the VO.21 national and international VO project actually participate in the IVOA, that has the mission to “facilitate the international coordination and collaboration necessary for the development and deployment of the tools, systems and organizational structures necessary to enable the international utilization of astronomical archives as an integrated and interoperating virtual observatory".The IVOA encourages observatories, universities, and astronomy projects worldwide to become involved in the VO as data, information, and computational service providers, and as consumers of the enriched, multiwavelength view of the Universe.In this poster we describe IVOA organization and current status of the VO in terms of tools, available data and standards. We present also the IVOA tools and activities developed for astronomy outreach and education.

## Assessing the NUV variability of stars across the spectral sequence

Bertone, Emanuele

Intensity and variability of the stellar ultraviolet radiation is one of the main variables that affect the space weather of planets and determine their conditions of habitability.We present a thourough study of the variability of stars of all spectral types in the near ultraviolet band (NUV), by using data from the GALEX-CAUSE survey of the Kepler field.The whole Kepler field was observed in the NUV band (1771-2931 angstrom), during 46 days in 2012 AugustSeptember, using 300 GALEX orbits, funded by Cornell University  (PI J. Lloyd). We constructed a large photometric catalog of light curves of more than 400,000 stars of all spectral types, that we used to determine the flux variability as a function of spectral type.Through the use of diagnostic diagrams we are also able to characterize the kind of variability of these objects. Preliminary results indicates a median NUV flux variability of 11% for solar analogs.

## New eyes on planet-disk interactions

Bertrang, Gesa H.-M.

The circumstellar disk around the Herbig Ae/Be star HD169142 is a well-studied object which shows structures on multiple wavelength ranges. Moreover, HD169142 harbors the most promising proto-planet candidate._x005F We present new SPHERE/ZIMPOL data which distinctly deviate from the established picture developed for this object. Based on these new observations as well as high-resolution ALMA observations and further archival data, we built a new model for this disk. These new eyes, namely SPHERE and ALMA, in combination with 3D radiative transfer simulations strongly indicate that we are witness to previously undetected planet-disk interactions in HD169142.

## Magnetic fields and polarimetry in planet-forming disks

Bertrang, Gesa H.-M.

Understanding the physical processes in planet-forming disks is vital for the understanding of planet formation. It has been predicted that magnetic fields are an important factor on a wide range of these mechanisms, such as the migration of planet(esimals) and the mere evolution of disks. Yet, observational constraints are still pending. In the classical picture, (sub-)mm continuum polarization is the tracer for magnetic fields in disks. Aspherical dust grains, whose thermal emission is intrinsically polarized, get aligned by the magnetic field due to radiative torques. In recent years, however, this picture has been challenged. New theoretical studies show that (sub-)mm continuum polarization can also be created by scattering of the thermal dust emission or arise from aspherical grains which are aligned by the radiation field rather than the magnetic field. These three mechanisms trace fundamentally different physics in protoplanetary disks, yet, their polarization predictions are not clearly distinguishable. I will give an outlook on how to disentangle the sources of continuum polarimetry with ALMA by applying spectro-polarimetry, and present the first predictions for linear line polarization in disks.

## Laboratory simulation of astrophysical jets within facilities of Plasma Focus type

Beskin, Vasily

A laboratory simulation of astrophysical processes is one of the intensively developed areas of plasma physics. A new series of experiments has been launched recently on the Plasma Focus type facility in NRC Kurchatov Institute. The main goal is to study the mechanisms of the jet stabilization, due to which it can propagate at distances much greater than their transverse dimensions. The experiments with stationary gas filling revealed regimes in which a narrowly collimated plasma jet was formed, the head of which was no wider than several centimeters at jet propagation distances of up to 100 cm. The PF-1000 (IFPiLM, Warsaw, Poland) and KPF-4 (SFTI, Sukhum, Abkhazia) experiments are aimed at creating profiled initial gas distributions to control the conditions of plasma jet propagation in the ambient plasma. Estimations of the dimensionless parameters, i.e. the Mach, Reynolds, and Peclet numbers which were achieved during the experiments, showed that the PF-facilities can be used for the YSO jets modelling. Thefuture experiments, which can allow one to understand the nature of the stable plasma ejections observed in many astrophysical sources, are discussed.

## Radio pulsar alignment/counter-alignment - final test?

Beskin, Vasily

At present, there are theoretical models of radio pulsar evolution that predict both the alignment, i.e. evolution of inclination angle between magnetic and rotational axes to zero degree and its counter-alignment, i.e. evolution to 90 degree. At the same time, both models describe well the pulsar distribution on the P–P diagram. For this reason, up to now it was impossible to determine the braking mechanisms since it was rather difficult to estimate the evolution of the inclination angle for individual pulsar based on observations. In this poster, we demonstrate that the statistics of interpulse pulsars can give us the key to solve the alignment/counter-alignment problem as the number of interpulse pulsars drastically depends on the evolution of the inclination angle.

## Faint Dwarf galaxies in nearby WINGS clusters: photometric characterization

Bettoni, Daniela

In the cores of galaxy clusters there is a population of lows-mass stellar systems such as dwarf Early-type galaxies, ultra-compact dwarf galaxies (UCDs) and ultra diffuse dwarf galaxies. We present here the photometric and morphological characterization of this population of objects using deep CFHT images of a sample of clusters belonging to the WINGS survey (0.04<z<0.06).we study="" only="" galaxies="" that="" are="" spectroscopically="" confirmed="" members="" of="" the="" cluster.="" population="" dwarfs="" ranges="" from ="" ~30%="" for="" more="" rich="" clusters="" to ="" ~5-6%="" less="" ones.="" we="" found="" a="" red="" and="" blue="" discuss="" their="" properties="" in="" comparison="" with="" cluster="" characteristics.="" finally="" this="" sample="" compared="" data="" from="" nearby="" as="" virgo="" coma.="" implications="" mechanisms="" formation="" dwarf="" systems="" briefly="" discussed.<="" p="">
</z&lt;0.06).we&gt;</p>

## Quasar activity in the neighboring Universe

Bettoni, Daniela

We analyzed the properties of the close environments of a sample of low redshift quasarsto investigate the role of interactions for triggering and fueling the QSO phenomenon.We present the results of an extensive spectroscopic campaign at GTC and NOT telescopes in La Palma aimed at deriving the properties of companion galaxies of quasars anddetecting signatures of recent star formation both in the host galaxies and in the companion galaxies.The sources are drawn from a large (~400) sample of  (z<0.4) quasars extracted from the SDSS "Stripe 82" for which we previously investigated the host galaxies and the large scale environments properties.We found that the close (<100 kpc) companion galaxies are often associated to the QSO but  only a modest recent star formation is present. The implications for the mechanisms ofnuclear activity are briefly discussed.

## Elemental abundances of primary stars in Sirius-like systems: Constraints on pollution from AGB stars

Bharat Kumar, Yerra

Study of primary stars lying in Sirius-like systems with various masses of WD companions and orbital separations is one of the key aspects to understand the origin and nature of Barium (Ba) stars, wherein enhanced carbon and/or s-process elements are suggested through mass transfer from AGB companions. We have analysed chemical composition of 21 FGK primaries, including dwarfs and giants, systematically using good quality high resolution spectra. Three Ba dwarfs are discovered which provides the first direct evidence of Ba dwarfs are with WD companions. On the other hand, absence of s-process enrichment is observed in stars even their companion WD mass is large enough to produce these elements during their TP AGB phase. Surface abundances of s-process elements in our sample are compared with AGB models of respective masses estimated from their WD masses. Results suggest s-process enrichment in sample Ba dwarfs follow McClure hypothesis similar to Ba giants. A few conclusions are drawn from this study: large mass of WD (>0.51 Msun) is not only the sufficient condition to form a Ba star, orbital separation is not main constraint to differentiate between strong and mild Ba stars, and different levels of s-process abundances among Ba stars may not be dominated mainly by the metallicity.

## Time-series analyses of Cepheid and RR Lyrae variables in the wide-field variability surveys

Bhardwaj, Anupam

Stellar variability studies are undergoing a renaissance with many large ongoing or soon to start surveys that focus on exploring time-domain in addition to multi-wavelength and wide-area approach. Cepheid and RR Lyrae are pulsating variable stars that are both primary standard candles and tracers of the stellar populations and structure of the host galaxy. These variables provide a unique opportunity to explore strong constraints for stellar pulsation models by an extensive comparison of theoretical and observed light curves and their pulsation properties. We present a detailed light curve analysis of Cepheid and RR Lyrae variables with the largest observational dataset derived from the time-resolved wide-field variability surveys. A quantitiative and multiwavelength comparison with the theoretical models, generated from the stellar pulsation codes, provides stringent constraints for the input parameter space, such as the mass-luminosity relations, to the pulsation models. We further discuss the impact of convective efficiency and opacity in pulsation models on the light curve structure and pulsation properties of Cepheid variables. We will also present results of Cepheid and RR Lyrae stars from the near-infrared time-series surveys of the Large Magellanic Cloud (LMCNISS) and the Milky Way (VVV) and discuss multiband Period-Luminosity relations and their application to extragalactic distance scale. In the era of ELT(s), these fundamental tests between theory and observations will be more feasible and will help in advancing our understanding of the theory of stellar evolution and pulsation.

## Solar variability and climate change – an Empirical Analysis

bhargawa, asheesh

Sun in the main source of energy for our planet therefore even a slight change in its output energy can make a huge difference in the climatic conditions of the Earth. The rate of energy coming from the Sun (solar irradiance) might affect our climate directly by changing the rate of solar heating of the Earth and atmosphere and indirectly by changing cloud forming processes. In the present paper, based on stability test of the Vector autoregressive (VAR) model, we have used impulse response functions and variance decomposition method for the analysis of climate variability. We have examined the possible connection between the solar irradiance and some climate indicators, viz., the global temperature anomaly, the global mean sea level, global sea ice extent and the global precipitation anomaly since last forty years (1978-2017). We have noticed that these parameters have shown changing patterns during the last few decades. In addition, we have also tried to find the role of atmospheric carbon dioxide as a greenhouse gas in the climate change. Considering global surface temperature anomaly (land + sea) as the most important indicator of clime change and using the impulse response function analysis and variance decomposition method, we have tried to answer the questions whether the climate system is subjecting to a solar irradiance shock or what is the contribution of rise in CO2, etc?

## Studying the high redshift universe combining JWST and the power of gravitational lensing

Bhatawdekar, Rachana

Exploring the very first galaxies is one of the major contemporary problems in astronomy. We do not know when the first galaxies formed, nor how their formation occurred. The James Webb Space Telescope (JWST) will be launched between March and June of 2019 and will search for the First Light objects in the redshift range of z=10-15. Reaching these galaxies will be routine with JWST, however, until then, our best chance to study these systems is through deep observations of lensing clusters with the Hubble Space Telescope (HST) by using them as Cosmic Telescopes'. Therefore, to extend its reach even farther beyond its technical capabilities before JWST is launched, the HST is observing six massive clusters of galaxies as gravitational lenses to find the faintest and earliest galaxies in the Universe, ~10-100 times fainter than any previously studied, as a part of the Hubble Frontier Fields (HFF) program. In this talk, I will present how we detect and examine the objects behind HFFs lensing cluster MACSJ0416.1-2403, Abell 2744 and their parallel fields. We have developed a novel method to subtract the massive galaxies from these clusters, allowing for a deeper and cleaner detection of the faintest systems. We present a photometric study of distant z>5 galaxies using all 10 bands available for Frontier Fields (HST, Spitzer and K-band). From this, we have derived the first galaxy stellar mass function (GSMF) at z > 5 for Frontier Fields program. I will further discuss how these results reveal new information on the faint-end of the mass function from the faintest galaxies at high-z, unveiling the potential science that can be done with JWST data.

## The evolution of galaxy stellar mass functions at z = 6-9 in the Hubble Frontier Fields

Bhatawdekar, Rachana

Exploring the very first galaxies is one of the major contemporary problems in astronomy. We do not know when the first galaxies formed, nor how their formation occurred. The James Webb Space Telescope (JWST) will be launched between March and June of 2019 and will search for the First Light objects in the redshift range of z=10-15. Reaching these galaxies will be routine with JWST, however, until then, our best chance to study these systems is through deep observations of lensing clusters with the Hubble Space Telescope (HST) by using them as Cosmic Telescopes'. Therefore, to extend its reach even farther beyond its technical capabilities before JWST is launched, the HST is observing six massive clusters of galaxies as gravitational lenses to find the faintest and earliest galaxies in the Universe, ~10-100 times fainter than any previously studied, as a part of the Hubble Frontier Fields (HFF) program. In this talk, I will present how we detect and examine the objects behind HFFs lensing cluster MACSJ0416.1-2403, Abell 2744 and their parallel fields.  We have developed a novel method to subtract the massive galaxies from these clusters, allowing for a deeper and cleaner detection of the faintest systems. We present a photometric study of distant z>5 galaxies using all 10 bands available for Frontier Fields (HST, Spitzer and K-band). From this, we have derived the first galaxy stellar mass function (GSMF) at z > 5 for Frontier Fields program. I will further discuss how these results reveal new information on the faint-end of the mass function from the faintest galaxies at high-z, unveiling the potential science that can be done with JWST data.

## Multi-wavelength intraday variability studies: what do they tell us about blazar Jets?

Bhatta, Gopal

Intraday variability studies are the most important, if not the only, tools to explore the physical processes occurring at the innermost blazar regions which are not resolved by any current instruments. In this presentation, we report the results of intraday variability in the optical (BVRI bands) and hard X-ray band (3-79 keV) in a number of blazars consisting of both BL Lacs and flat spectrum radio quasars. In the optical microvariability studies of low-synchrotron peaked blazars S5 0716+714 and BL Lac, we observed many interesting features such as rapid variability, large variability amplitude, presence of characteristic timescales, bluer-when-brighter achromatic behavior, and single power-law power spectral density. In 31 NuSTAR observations of 13 blazars, using spectral and timing analysis, we found similar features consistent with the ones from the optical studies. In addition, in BL Lacs we estimated the Lorentz factor of the population of highest energy electrons emitting synchrotron emission, and whereas in flat-spectrum radio quasars, using external Compton models, we estimated the energy of the lower end of the injected electrons to be a few Lorentz factors. In addition, we find that the low flux state exhibit more rapid variability in contrast to the previously reported results showing high flux states displaying rapid variability. In both the studies, the size of the emission regions estimated using variability timescales turn out to be an order magnitude smaller than the gravitational radius of a typical black-hole masses between 10^8-10^9 solar masses which are believed to be harbored by the radio-loud AGN. The results of the studies suggest that these low-amplitude rapid variability might originate as a result of magnetohydrodynamical instabilities near the base of the jets triggered by the processes modulated by the magnetic field at accretion disc.

## WFIRST Microlensing Exoplanet Characterization with HST Follow up Astrometry

BHATTACHARYA, APARNA

More than 50 planets are discovered with the different ground based telescopes available for microlensing. But the analysis of ground based data fails to provide a complete solution. To fulfill that gap, space based telescopes, like Hubble space telescope and Spitzer are used. My research work focuses on extracting the planet mass, host star mass, their separation and their distance in physical units from HST Follow-up observations. I will present the challenges faced in developing this method.This is the primary mass measurement method to be used for NASA's top priority project (according to 2010 decadal survey) Wide Field InfraRed Survey Telescope (WFIRST) Exoplanet microlensing space observatory, to be launched in 2025. The unique ability of microlensing is that with WFIRST it can detect sub-earth- mass planets beyond the reach of Kepler at separation 1 AU to infinity. This will provide us the necessary statistics to study the formation and evolution of planetary systems. This will also provide us with necessary initial conditions to model the formation of planets and the habitable zones around M dwarf stars.

## Developing Astronomical Skills in Nepal

Bhattarai, Suresh

Developing Astronomical Skills in Nepal (DASN) is a new initiative at Nepal Astronomical Society (NASO) designed for undergraduate students in Nepal. It aims to motivate undergraduate students for project works in space science/astronomy/astrophysics and help during their project/research work.This paper aims to share the progress of the initiative and highlights the importance of the Information and Communication Technology (ICT) for the implementation of this challenging initiative in Nepal. The challenges we faced during the communication to different colleges for the participation will also be shared. Our strategic approach to have active role of each colleges of the participants in the initiative will be explained. It will also share how we are integrating this program to promote capacity building in each of the seven federal states of Nepal.

## Spatial variations of scattering polarization signatures at sugranular scales

Bianda, Michele

The scattering polarization signals measured in the Sr I 460.7 nm spectral line on the solar disk are usually an average over a surface area exceeding the typical granular size. Variation in intensity and orientation of the magnetic field plus spatial and temporal variations in the plasma properties are expected to cause variations in the amplitude and orientation of the scattering polarization measured at subgranular scales. The Hanle effect and anisotropies in the radiation field are the origin of these modifications. The measurement of these variations is challenging, because high polarimetric precision and high spatial resolution are needed at the same time. However, the diagnostic potential of these measurements is promising. We report here first successful observations performed using the ZIMPOL polarimeter at the GREGOR solar telescope on Tenerife.

Bieryla, Allyson

## FOSSILs in the Galactic Halo

Grillmair, Carl

We use a matched filter to detect compact groups of old, metal-poor stars that we term FOSSILs (Fragments of Old Stellar Systems In Limbo). With size scales on the order of 10 arcminutes, distances ranging from 2 to 200 kpc, and memberships ranging from a handful to several dozen stars, these FOSSILs stand out from the surrounding field and are presumably signatures of, or debris from, ancient star clusters and dwarf galaxies. They may be localized concentrations of stars within more extensive tidal streams, and in several cases may be the signatures of extant but heretofore undetected ultrafaint galaxies. Using magnitudes and colors from the Pan-STARRs survey, we detect 140 such FOSSILs at 5σ or greater in a 2200 square degree region in the vicinity of the north Galactic pole. Spectroscopic and astrometric follow-up of these FOSSILs will be required to determine the nature of these structures, deepen our understanding of the make-up and accretion history of the Galactic halo, and perhaps alleviate the missing satellites problem.

## Observing Pop. III Stars with HARMONI and the E-ELT

Grisdale, Kearn

Instruments like HARMONI on the E-ELT will likely be able to observe the first spatially resolved spectra of the very earliest (z~10) galaxies. Contained within these spectra will be details of the very first and as of yet unobserved stars, i.e. Population III stars. Detecting the emission from Pop. III stars would provide significant insight into star formation, galaxy formation and evolution in the early Universe. Using New Horizon, an AMR-hydrodynamical cosmological simulation, in combination with published SEDs for Pop. III stars and full radiative transfer (i.e. the Yggdrasil Models and CLOUDY look-up tables respectively) I am able to compute and simulate the flux of the He II 1640Å line, a tracer of the presence of Pop. III stars, produced by the simulation. Mock observations of these galaxies can then be used to provide insight into whether these stars are observable and which of their physical properties will be determined by the HARMONI and E-ELT. In this talk I will demonstrate:How mock observations of Pop. III stars can be producedWhat physical properties of Pop. III stars can be determined from observationsHow such observations can be used to rule out different PopIII models when combined with real observations from the HARMONI on the E-ELT

## Emission and Absorption lines: the keys to unlocking galaxy properties

Grisdale, Kearn

Within the the next decade, instruments like HARMONI on the E-ELT will routinely provide spatially resolved spectra of high redshift (z~2-3) galaxies. Analysis of these spectra, via both emission and absorption lines, will provide a detailed look into the physical properties of these early galaxies. We have developed a method for simulating the emission line flux in H-alpha for large number (~20) of galaxies found in New Horizon, an AMR-hydrodynamical cosmological simulation, at a range of different redshifts. Using this library of mock observations, we can start to look into the statistical properties of the galaxy population (e.g. distribution of v/sigma as a function of mass, luminosity, redshift). Furthermore, mock observations provide a means of testing different "sub-grid physics" in the cosmological models by making predictions of what observational signatures will result from different choices.  These simulations will drive the development of key observing programmes for HARMONI.

## Experimental light scattering by ultrasonically controlled small particles

Gritsevich, Maria

Electromagnetic scattering is a fundamental physical process that allows inferring characteristics of an object studied remotely. This possibility is enhanced by obtaining the light-scattering response at multiple wavelengths and viewing geometries, i.e., by considering a wider range of the phase angle (the angle between the incident light and the light reflected from the object) in the experiment. Planetary environments represent numerous examples of scattering media composed of particles. There is a fundamental difficulty, however, in bridging the gap between the light-scattering theory and experiment: while existing theoretical models can be used reliably to simulate scattering by a fixed finite object or random particles, thorough experimental work has mostly been performed with light scattered from surfaces. We present an overview of our newly developed 3D scatterometer — a setup for precise multi-angular measurements of light scattered by mm- to µm-sized samples held in place by sound. The measurements obtained with the scatterometer can be cross-validated against the modeled light-scattering characteristics of the sample, i.e., the intensity and the degree of linear polarization of the reflected light, calculated with state-of-the-art electromagnetic techniques.

## Consequences of meteoroid impacts based on atmospheric trajectory analysis

Gritsevich, Maria

One of the important steps in the prediction of an impact threat to Earth raised by potentially hazardous asteroids is the understanding and modeling of the processes accompanying the object’s entry into the terrestrial atmosphere. Such knowledge enables characterization, simulation and classification of possible impact consequences. For observed meteor events the reconstructed atmospheric trajectory is the key to deriving the pre-impact meteoroid's orbit in the Solar System on one hand, while on the other hand, it is also required for dark flight simulations which enables to locate surviving meteorite fragments on the ground. Using dimensionless expressions, which involve the pre-atmospheric meteoroid parameters, we have built physically based parametrisation to describe the changes in mass, height, velocity and luminosity of the object along its atmospheric path. The developed model is suitable to estimate a number of crucial unknown values including the shape change coefficient, ablation rate, and surviving meteorite mass. The model is also applicable in the  prediction of the terminal height of the luminous portion of flight and therefore, the duration of the fireball. Besides the model description, we demonstrate its application using the wide range of observational data from meteorite-producing fireballs appearing annually (such as e.g. the Annama, Košice, Neuschwanstein and Osceola fireballs) to larger scale impacts (such as the Chelyabinsk, Sikhote-Alin and Tunguska event). In particular, this approach enabled us to successfully recover the Annama meteorite based on the analysis of the fireball observed by the Finnish Fireball Network on 19 April 2014.

## The longest period Long Period Variables in the Magellanic Clouds

Groenewegen, Martin

There are thousands of Long Period Variables known in the Magellanic Clouds mainly due to microlensing surveys like MACHO, EROS and OGLE. However these variability surveys in the optical miss the reddest stars on the asymptotic giant branch as high mass-loss rates will obscure them. We have used the multi-epoch nature of the VISTA Magellanic Cloud (VMC) survey in the K-band in combination with literature data to look for very red AGB star variables. We discuss the results of this program that has revealed several stars with Mira-like amplitudes and periods beyond 1000 days.

## On the nature and mass loss of Bulge OH/IR stars

Groenewegen, Martin

We report on the succesful search for CO (2-1) and (3-2) emission associated with OH/IR stars in the Galactic Bulge. We observed a sample of 8 extremely red AGB stars with the APEX telescope and detected seven. The sources were selected at sufficient high galactic latitude to avoid interference by interstellar CO, which hampered previous studies of inner galaxy stars._x005F To study the nature of our sample and the mass loss we used VizieR and further literature study to collect photometric data and Spitzer IRS spectroscopy to construct the SEDs. In a first step we apply radiative transfer modelling to fit the SEDs and obtain luminosities and dust mass loss rates (MLR). Through dynamical modelling we then retrieve the total MLR and the gas-to-dust ratios. We derived variability periods of our stars from the VVV and WISE surveys. The luminosities range between approximately 4,000 and 5,500 Lsun and periods are below 700 days. The total MLR ranges between 10-5 and 10-4 Msun/yr. Comparison with the Vassiliadis & Wood (1993) evolutionary models shows that the progenitor mass is approximately 1.5 Msun, similar to the Bulge Miras and are of intermediate age (3 Gyr). If more massive OH/IR stars are rare in the Bulge this may explain the scarcity of Bulge carbon stars. The gas-to-dust ratios are between 100 and 400 and are similar to what is found for OH/IR stars in the galactic Disk. We will discuss the nature of this OH/IR population in view of the inner Galaxy stellar populations._x005F One star, IRAS 17347-2319, has a very short period of approximately 300 days which may be decreasing further. It may belong to a class of Mira variables with a sudden change in period as observed in some Galactic objects. It would be the first example of an OH/IR star in this class and deserves further follow-up observations.

## The colours of AGB stars in the JWST filters

Groenewegen, Martin

In Groenewegen & Sloan (2017) we have fitted the SEDs and IRS spectra of almost 400 AGB stars in the Magellanic Clouds and determined luminosity, dust mass-loss rate, and dust properties._x005F This sample covers essentially all phases of AGB evolutions, from low to extreme mass-loss rates and for oxygen-rich and carbon-rich chemistry._x005F As a by-product we calculated the synthetic magnitudes in essentially all filters of the various JWST instruments. This may be helpfull in understanding the observations of resolved stellar populations.

## A Sequential Estimation Approach to Determining Terrestrial Reference Frames

Gross, Richard

The Jet Propulsion Laboratory (JPL) is pursuing an approach to determining ITRF-like terrestrial reference frames based upon the use of a Kalman filter/smoother. Kalman filters are commonly used to estimate the parameters of some system when a stochastic model of the system is available and when the data contain noise. For the purpose of determining a terrestrial reference frame, the system consists of the positions and velocities of geodetic observing stations and associated EOPs along with their full covariance matrices. The data consist of time series of observed VLBI, SLR, GNSS, and DORIS station positions and EOPs along with the data measurement covariance matrices. In addition, measurements from ground surveys of the positions of reference marks of co-located stations are used as constraints to tie the technique-specific measurements to each other. JPL's Kalman filter and smoother for reference frame determination (KALREF) combines these measurements to determine ITRF-like reference frames subject to constraints imposed on the allowed evolution of the station positions. KALREF includes options to model the station motion as linear, linear and annual, or linear, annual, and semiannual. Through the use of stochastic models for the process noise, the station positions can be constrained to follow these models of the station motion (by setting the process noise to zero), to recover the observed station positions (by setting the process noise to a large value), or to follow a smoothed path (by setting the process noise to some intermediate value). The sequential estimation approach to determining terrestrial reference frames that is being pursued at JPL will be described along with its use to determine JTRF2014, JPL's realization of a terrestrial reference frame using the ITRF2014 input data sets.

## Tiny SXR solar flares observed by SphinX

Gryciuk, Magdalena

The Solar Photometer in X-rays (SphinX) was designed to observe soft X-ray solar emission in the energy range between ~1 keV and 15 keV with the resolution better than 0.5 keV. The instrument operated from February until November 2009 aboard CORONAS-Photon satellite, during the phase of exceptionally low minimum of solar activity. Despite a very low activity 1604 small X-ray events have been recognized by semi-automatic inspection of SphinX light curves. The SphinX Flare Catalogue not only contains the time of maximum occurance, but also other ?are characteristics. Results of the statistical analysis of the catalogue data are presented.

## Meteor detection from the Fireball Moroccan Network: First orbital results and links to parent bodies

guennoun, meryem

We are about to develop in Morocco, several stations of observations supplied with two different types of cameras (All-Sky cameras and oriented watec cameras). Three All sky cameras are already installed respectively in Beni Mellal, Oukaimeden and Meknès, and two watec cameras are installed in Oukaimeden and Marrakech. We are planning to expand our Network by installing more cameras in many other locations in Moroccan territory. In this work, we are going to present orbital results of the watec double station. We computed the direction of these two cameras using the method of Rendtel et al. (2014). The aim of this project is to compute meteor trajectories and find a link to their parent bodies. Several parent bodies were linked to observed meteors, such as the comet « swift Tuttle » during Perseids observations on 2014 year. One similarity with the 252P/LINEAR comet was linked to one orbit in the Sonotaco 2009 meteor database. Here we present our first results.

## The impact of flares and CMEs on planetary atmospheres

Guenther, Eike

Recent studies have shown that planets in the mass-range between 2 and 400 MEarth have a huge spread in densities. Even planets of the same mass can have very different densities. How can this diversity be explained? In the first 100 million years of their evolution, planets are exposed to strong EUV and X-ray (XUV) radiation from the host star. Observations, and theoretical models have shown that such radiation can lead to the erosion of planetary atmospheres. This process naturally explains the diversity of planets: Planets with atmospheres have low densities, planets without atmospheres have high densities. If this idea of atmospheric erosion were correct, it would have important consequences for the habitability of planets, since planets without atmospheres cannot be habitable. The erosion of planetary atmospheres is particularly important for potentially habitable planets of M-stars, because they orbit at very short distances from the host stars were the erosion is particularly strong. In recent years it became clear that the quiescent XUV-radiation is usually not strong enough to erode the atmospheres of planets completely. However, very little is known about the impact of flares and coronal-mass ejections (CMEs) on planetary atmospheres within the first 100 million years of their evolution. The situation is particularly difficult for CMEs, as only very few such events in young M-stars have been observed. Thanks to the new instrumentation, it is now possible to determine the flare-rate for young M-stars, and to study also the CMEs. Using data obtained with the Kepler satellite, we determine the statistics of flares of more than 100 M-stars with an age of 17 Myrs, and determine the power-law index of the flare-distribution. We also obtained more than 1000 high-resolution spectra of active M-star to study the properties of CMEs, and compare them with CMEs observed on the Sun.

## The AMBRE Project: r-process element abundances in the Milky Way thin and thick discs

Guiglion, Guillaume

Chemical evolution of r-process elements in the Milky Way disc is still a matter of debate. We took advantage of high resolution HARPS/UVES/FEROS spectra from the ESO archive in order to derive precise chemical abundances of 3 r-process elements Eu, Dy & Gd and also Ba abundance, for more than 1000 stars. The chemical analysis has been performed thanks to the automatic optimization pipeline GAUGUIN. Based on the [alpha/Fe] ratio, we chemically characterized the thin and the thick discs. We present and discuss chemical abundance patterns of such elements in both discs.

## When our Sun was Young: Coronal X-ray, TR-Chromospheric UV Emissions, Flares and Winds of the Young Sun (and solar-type stars) and Effects on Hosted planets.

Guinan, Edward

Studies of young solar proxies (G0-G5 V stars), as part of the Sun in Time'' program, show that the young Sun was rotating over ten times faster than today. As a consequence, these young sola -type stars (including the young Sun) had vigorous magnetic dynamos and correspondingly strong coronal X-ray and EUV emissions and chromospheric FUV and UV emissions - up to several hundred times stronger than that observed for the present Sun. Also, observations of the youngest solar proxies indicate that the young Sun had frequent and powerful flares and most likely significant winds. This paper is an update of the earlier studies by Ribas et al. (2005: ApJ.,622, 680; Guinan and Engle (2009: IAUS, 258, 395) with the addition of data from more recent stellar wind and flare studies (see Guinan and Engle 2015: IAUGA 2255511;  Airapetian & Usmanov 2016: ApJ, 817L.,24; Pognan et al. 2018: arXiv180205153 and references therein). This study focuses the first ~4.5 billion years of the Sun’s post-PMS life and also applies to other solar-type stars.The recent results of the Sun in Time'' program will be discussed that show the decline of solar X-UV fluxes, winds and flares with slower rotation and increasing age. The determination of the flare energies and frequencies and stellar winds based on recent studies are presented. We present our most recent Age-Rotation-Activity relations for solar-type stars that also can be used in the study of other solar-type stars with planets (e.g. tau Ceti). Also briefly discussed are some of the major effects that the young Sun's strong magnetic activity had on the photoionization, photochemistry, and erosion of paleo-planetary atmospheres as well as on the development of life on these planets.This research is supported by grants from NASA and NSF which we gratefully acknowledge.

## Growing Plants on Mars - Mars Gardens in the University: Growing Vegetables in Martian regolith simulant.

Guinan, Edward

Over the next few decades NASA and private enterprise missions such as SpaceX-Mars plan to send human missions to Mars with the ultimate aim to establish a permanent human presence on this nearby planet. For a self-sustaining colony on Mars it will be necessary to provide food by growing plants in heated/sheltered greenhouses. As part of an undergraduate student project in Astrobiology at Villanova University, experiments are being carried out, testing how various plants grow in the Martian regolith (soil).  The plants are being grown and tested in Mars regolith simulant commercially available from The Martian Garden (TheMartianGarden.com). This Mars regolith simulant is based on Mojave Mars Simulant (MMS) developed by NASA and JPL for the Mars Phoenix mission. The MMS is based on the iron-rich Mojave Saddleback basalt. Additional reagents were added to this iron-rich basalt to bring the chemical content close to the actual Martian regolith. It is ~90% similar to regolith found on the surface of Mars - excluding poisonous perchlorates commonly found on actual Mars surface. Since Mars is 1.52 a.u. from the Sun, the ambient surface solar light insolation is about ~43% Earth.A wide variety of plants and vegetable are being grown and tested. These include carrots, spinach, dandelions, kale, soy beans, peas, onions, garlic, peanuts, Jerusalem artichokes, and of course potatoes, and sweet potatoes. In Spring 2018 barley and hops have been planted in the MMS in larger quantities with the hope of making Martian beer. Also earthworms and red worms have been introduced to test their viability. The worm castings (excrement) will be used to enrich the Martian soil. The results of this project will be discussed from an educational viewpoint as well as from usefulness in Martian botany research.We thank the Dept. of Astrophysics and Planetary Science (Villanova University) for financial support and the Biology Department for the use of their campus greenhouse.

## Hypothesis of the massive planet on the periphery of the Solar System

Guliyev, Rustam

The present work reviews selected aspects of the Guliyev's hypothesis about the massive celestial body at a distance of 250-400 AU from the Sun as well as the factor of comets transfer. It is shown, that the conjecture of the point around which cometary perihelia might be concentrated, is not consistent. On the issue of perihelia distribution, priority should be given to the assumption that there is a plane or planes around which the concentration takes place. The search engine for such planes was applied to numerous cometary groups, separated by clusters T (discover date), e, q, H (absolute magnitude), Q, 1/aori, etc. A total of 24 comet groups were investigated. In almost all cases there are detected two types of planes or zones: the first one is very close to the ecliptic, another one is about perpendicular to it and has the parameters: ip = 86°, Ωp = 271.7°. The existence of the first area appears to be related to the influence of giant planets. The Guliyev's hypothesis says that there is a massive perturber in the second zone, at a distance of 250-400 AU. It shows that number of aphelia and distant nodes of cometary orbits in this interval (within statistical confidence) significantly exceeds the expected background. On the basis of collected cometary data, we have estimated orbital elements of the hypothetical planetary body: a = 337 AU; e = 0.14; ω = 57°; Ω = 272.7°; i = 86° Naturally, each value may contain some errors. In order to test the stability of such an orbit, the planet was integrated for 10 million years, assuming that its mass is about 10 Earth masses. The orbits of 33 comets (having aphelia and distant nodes 286-388 AU) are also integrated in the past for a million years in order to trace possible dynamic relationship with the planet. In doing so, we varied the mean anomaly of the planet from 0° to 360° by 10° in each cycle of numerical explorations.

## Multi-wavelength Variability and QPOs in Blazars

Gupta, Alok

In the present poster, I will summarize our recent results based on multi-wavelength variability and QPOs detection in blazars.

## GENERAL FEATURES OF THE SOLAR CYCLE 24

Gursoy, Fulin

In this study, using the data of Istanbul University Observatory, general features of the Solar Cycle 24 are presented.

## Zooming into the AGN properties with Space VLBI

Gurvits, Leonid

Investigation of the physics of the AGN phenomenon requires, among other methods, ultra-high angular resolution, offered in radio domain by Very Long Baseline Interferometry (VLBI). The extension of VLBI into space with baselines exceeding the Earth diameter offers the highest achievable today angular resolution reaching single-digit microarcseconds. The Space VLBI mission RadioAstron which operates in orbit since 2011 completed the observational part of its AGN Survey project in 2017. The Survey sample includes 247 sources observed at 5 and partially 1.6 GHz over the total of 2000 hours. The observations were conducted in the non-imaging mode at the baselines ranging from several to 27 Earth diameters; the latter, at 6 cm wavelength provides the angular resolution of ~30 uas. Importantly, since the ability of an interferometer to tackle the highest brightness temperatures requires the longest physical length of a baseline, the RadioAstron offers a unique opportunity to measure directly the brightness temperatures exceeding the value of 1011.5 K, dictated by the Inverse Compton “catastrophe”. Indeed, such the ultra-high brightness has bee detected in several AGN. The presentation will discuss these results and their possible implications for the physics of the radio emission mechanism in AGN. Another result of the RadioAstron AGN Survey project is a pioneering detection of refractive scattering of radio emission in the interstellar medium. This is a long predicated phenomenon with manifestations reachable only with baselines exceeding the Earth diameter. We will discuss how the presence of refractive scintillations might impact estimates of physical parameters of AGN.The RadioAstron AGN Survey data are being analysed in concurrence with several ground-based observing programmes in radio and other domains of the electromagnetic spectrum. The presentation will review the current status of the overall RadioAstron AGN Survey data analysis and its perspectives

## Dust in Clusters: Separating the Contribution of Galaxies and Intracluster Media

Gutierrez, Carlos

Analyzing Herschel data for a large sample clusters of galaxies up to redshift 0.70 strong constraints ontheir mean intracluster emission of dust have been obtained; withina radius of 5 arcmin centered in each cluster, the 95% C.L. limits obtained are 86.6,48.2, and 30.9 mJy at the observed frequencies of 250, 350, and 500 micras. From theserestrictions, and assuming physical parameters typical of interstellar media in theMilky Way, we have obtained tight upper limits on the visual extinction of backgroundgalaxies due to the intracluster media (ICM): AV(95% C.L.) <~ 10^(-3) mag. Strongconstraints are also obtained for the mass of such dust; for instance, using the dataat 350 mum we establish a 95% upper limit of <10^9 Msun within a circle with aradius of 5 arcmin centered in the clusters. This corresponds to a fraction of thetotal mass of the clusters of 9.5 × 10^(-6), and indicates a deficiency in thegas-to-dust ratio in the ICM by about three orders of magnitude in relation to thevalue found in the Milky Way. Computing the total infrared luminosity of the clustersin three ranges of redshift (0.05-0.24, 0.24-0.42, and 0.42-0.71) and two ranges ofmass (<10^14 and >10^14 Msun), respectively, a strong evolution of luminosity inredshift (L ~ z^1.5) for both ranges of masses is found. The results indicate a strongdeclining in star formation rate with time in the last ~6 Gyr.

## Analytical studies of the dynamics of High-velocity clouds in the galactic halo of disk galaxies

Guzman, Consuelo Leona

Galactic evolution is strongly determined by outflows of hot baryons and infall of mainly neutral baryons, such as high velocity clouds (HVCs), which have been observed for many decades in the halo of our Milky Way. To describe the dynamics of HVCs analytically, Benjamin and Danly (1997) have solved numerically the equation of motion of a spherical cloud under the influence of gravity and drag force. Thus, they have been able to derive the terminal velocity of HVCs falling onto the Galactic disk. Here we show that their equation of motion can be solved analytically, by pure quadrature, so that even for more complicated and realistic gravitational potentials their dynamical behaviour can be studied in detail. The results presented here include a Miyamoto Nagai (1975) potential and an extended version by Barros et al. (2016). We show how the velocity changes as a function of height (also calculating the terminal velocity), including the Bernoulli effect, which leads to a lateral expansion of the HVC and thus to an increased drag. For a cloud falling into a density stratified halo from a distance of 5 kpc, supersonic velocities are reached at a height of 2.26 kpc, resulting in the formation of a bow shock. Using the model of Schulreich and Breitschwerdt (2011) we also calculate its precise position, as well as all the post shock fluid variables such as pressure, density and velocity. These analytical results will be compared to observations of Milky Way halo clouds.

## Circumstellar structures around high-mass X-ray binaries

Many high-mass X-ray binaries (HMXBs) are runaway systems, travelling through space with high velocities. Stellar wind and radiation of donor stars in HMXBs along with outflows and jets from accretors interact with the local interstellar medium and, under proper conditions, produce curious circumstellar structures. I will report the detection of several such structures and discuss their possible origin.

## ETV analysis of OGLE-IV eclipsing binaries

Hajdu, Tamás

We report a comprehensive study of the eclipse timing variation (ETV) of short periodic  (P1< 5d) eclipsing binaries (EB) derived from the photometric survey OGLE-IV. From the 450,000 EBs we selected approximately 9000 binaries which we found suitable for further examination. We sorted and analyzed the potential hierarchical triple candidates in an automatic manner and identified about half thousand systems which O-C diagrams show light-travel-time effect (LTTE). There are several studies about evolution of close binary systems however, if there is a further component it can significantly influence the orbital evolution of the inner components also in the early stage of their state. The large number of these potential candidate systems found by us makes it possible to do a meaningful statistical analysis of the outer orbit to understand better its effects on the close binaries. We found that (i) there is a significant lack of triple systems where the outer period is less than 400 days; (ii) in our sample of candidates there is no system with outer eccentricity higher than 0,8 , although such high eccentricity is not theoretically impossible; (iii) the distribution of the outer eccentricity has a maximum around e2=0,4.

## How Pulses in Short Gamma-Ray Bursts Constrain HMXRB Evolution

Hakkila, Jon

We present evidence that pulses in Short gamma-ray bursts (GRBs) originate from collisions between relativistically-ejected shells and slower-moving media (external shocks) rather than from collisions between shells of relativistically-ejected material (internal shocks). Using GRB/GW 170817A as a canonical example of a dying HMXRB system, we discuss how GRB pulse characteristics constrain the kinematics and structures of shocked regions produced in merging neutron star systems.

## Selection Biases and Gamma-Ray Burst Pulse Structure

Hakkila, Jon

Faint gamma-ray burst (GRB) pulses exhibit smoother, less structured light curves than bright GRB pulses. We demonstrate how low photon detection rates, noisy detectors, energy-dependent pulse characteristics, and temporal binning can all combine to smear out pre-existing complex pulse structures, converting them into the observed smooth triple-peaked pulse behavior. We then study bright GRB pulse light curves to avoid the biases, discovering that GRB pulses are characterized by time-symmetric emission structures overriding hard-to-soft spectral evolution. We describe how these observations greatly constrain GRB models.

## Inferring Progenitor Stellar Properties from Gamma-Ray Burst Pulse Characteristics

Hakkila, Jon

Pulses are the dominant form of prompt emission in gamma-ray bursts (GRBs). They are found in Short GRBs (merging compact systems), Long GRBs (collapsars), and x-ray flares (GRB afterglows). GRB pulses are characterized by triple-peaked light curves that evolve from hard-to-soft, with re-hardening occurring at or near the time of each peak; they are indicative of shocked material in relativistically expanding systems. Despite these similarities, Short GRB pulses differ from Long GRB pulses and x-ray flares in that they have shorter durations, shorter inter-pulse separations, and undergo more pronounced and rapid hard-to-soft spectral evolution. We discuss how these properties can be used to constrain characteristics of the GRB progenitors.

## Differentially rotating white dwarfs with 2DStars

Halabi, Ghina

The effect of stellar rotation is particularly interesting in accreting white dwarfs (WDs). Accreted material from a companion can transfer substantial angular momentum, thus spinning-up the WD [1]. Over five decades investigations [2,3] have shown that rapid rotation has a large influence on the stability of zero temperature WDs. Using 2DStars [4], a two-dimensional stellar evolution code, we investigate the evolution of the rotation profile on the nuclear time-scale of a rapidly differentially rotating cold WD [5,6]. The aim is to determine whether super-MChandrasekhar WDs can be brought into solid-body rotation due to the dissipative effects induced by the electron and turbulent viscosity, and explode as SNe Ia. We employ a fully relativistic equation of state for cold degenerate matter and start with an internal rotation profile that ensures sufficient differential rotation to avoid immediate collapse. _x005F _x005F References_x005F [1] Durisen R. H., 1977, ApJ, 213, 145_x005F [2] James R. A., 1964, ApJ, 140, 552_x005F [3] Ostriker J. P., Bodenheimer P., 1968, ApJ, 151, 1089 _x005F [4] Halabi, Izzard, Tout, Jermyn & Cannon, 2017, MmSAI, 88, 319H_x005F [5] Yoon S.-C., Langer N., 2004, A&A, 419, 623_x005F [6] Ghosh P., Wheeler J. C., 2017, ApJ, 834, 93

## Stellar feedback powering star-forming complexes in the Magellanic Clouds

Hamann, Wolf-Rainer

Clustered populations of massive stars have a big impact on their environment. They can create large structures like supergiant shells (SGSs) and superbubbles of shocked, X-ray emitting gas.  The formation of such structures is the direct result of stellar feedback  from the massive stars via strong ionizing radiation, stellar winds, and supernovae.Only detailed spectroscopic studies of the massive-star population can reveal the mechanisms that power their environment.  We performed exemplary studies on star-forming regions  in the supergiant shell SMC-SGS1 in the Wing of the SMC and in the complex  N206 in the LMC, which encloses an X-ray  'superbubble'.We obtained many hundreds of spectra with VLT FLAMES  of the massive star populations associated with each of the two mentioned complexes. Quantitative spectroscopic analyses were performed with the Potsdam Wolf-Rayet (PoWR) model atmosphere code, yielding  the stellar and stellar-wind parameters. The PoWR models then provide the ionizing flux and the mechanical feedback from each massive star.  Based on the total stellar feedback, the energy budget of the complexes is quantified and discussed. The star formation history is reconstructed from the distribution of stellar ages.The talk is focusing on massive stellar populations at different metallicities, obviously undergoing different modes of current star formation. The talk will highlight the role of feedback for the evolution of these dwarf galaxies.

## Abundance and kinematics of the CGM as observed with MUSE

Hamanowicz, Aleksandra

Galaxies are constantly fed by the diffuse material from the intergalactic medium through the Circum -  Galactic Medium (CGM). Strong outflows form SN or AGN feedback expel the enriched material back to the CGM. The physical properties of the CGM are still poorly unknown: is it a multi-phase medium, how powerful are inflows and outflows and how much mass is carried away by the galactic winds? We can probe these vast gaseous haloes around galaxies by studying absorbers detected in the spectra of the background bright quasars. To understand the dynamics of the system we combine the physical properties from the absorption features with the broader view of the absorber’s host and its environment by emission diagnostics, using the IFU spectroscopy.To address these questions we are studying a sample of absorber – quasar pairs with MUSE. In this talk I will present some preliminary results of this program, in particular focusing on the studies of the gas kinematics and metallicity and the general CGM properties of the quasar absorbers host galaxies, which in turn can help better constrain galaxy evolution models.

## Hot Jupiters from Alternative High-eccentricity Migration Scenarios

One of the proposed formation origins of hot Jupiters (HJs) is high-eccentricity (high-e) migration. In high-e migration, the eccentricity of the orbit of a planet initially beyond the ice line is dynamically excited, leading to strong tidal dissipation occurring near periapsis and eventually resulting in a tight orbit. Previously studied secular variants of high-e migration involve an inclined and/or eccentric binary companion (star or massive planet). However, the predicted formation rates are too low compared to observations, by a factor of ~ 10. Therefore, alternative scenarios are needed. Recently, an alternative scenario was proposed by Lithwick & Wu involving secular chaos with three or more planets. This scenario can potentially produce many HJs because the initial conditions to achieve high eccentricities are less stringent compared to the case of an inclined binary companion. Until recently, studies of this scenario were limited to small phase space due to the prohibitive nature of direct N-body integrations. Here, we present a new secular method to study the long-term dynamics of hierarchical systems composed of nested orbits, with an arbitrary number of bodies and structure. We use this method to study the formation of HJs driven by secular chaos in multiplanet systems. Also, we consider scenarios in which HJs are formed through high-e migration in stellar triple systems, and discuss how secular evolution suggests the presence of unseen planetary companions to hot Jupiters in stellar binaries.

## Galactic forces rule dynamics of Milky Way dwarf galaxies

Hammer, Francois

Dwarf galaxies populating the Galactic halo are assumed to host the largest fractions of dark matter,as calculated from their velocity dispersions. Their major axes are preferentially aligned with the VastPolar Structure (VPOS) that is perpendicular to the Galactic disk, and we find their velocity gradientsaligned as well. It suggests that tidal forces exerted by the Milky Way are distorting dwarf galaxies.Here we demonstrate on the basis of the impulse approximation that the Galactic gravitational accelerationinduces the dwarf line-of-sight velocity dispersion, which is also evidenced by strong dependencesbetween both quantities. Since this result is valid for any dwarf mass value, it implies that dark matterestimate in Milky Way dwarfs cannot be deduced from the product of their radius by the square oftheir line-of-sight velocity dispersion. This questions the high dark-matter fractions reported for theseevanescent systems, and the universally adopted total-to-stellar mass relationship in the dwarf regime.It suggests that many dwarfs are at their first passage and are dissolving into the Galactic halo. Itopens a promising way to estimate the Milky Way total mass profile at large distances.

## Heavy puzzle pieces: Learning about the i process from Pb abundances

Hampel, Melanie

The large majority of elements heavier than iron are formed by the slow (s) and rapid (r) neutron capture processes. However, it has become clear that a neutron capture process operating at neutron densities intermediate to the s and r process (i process) gives rise to its own characteristic abundance pattern. This i-process pattern is successful at reproducing observed heavy-element abundances that could not be explained previously, e.g. those of carbon-enhanced metal-poor stars that show enrichments of s- and r-process elements (CEMP-s/r). The required high neutron densities may occur in the thermal pulses of Asymptotic Giant Branch (AGB) stars as a result of proton ingestion episodes. However, the sites of the i process are as yet unknown.Comparing theoretical predictions of i-process nucleosynthesis with the observed abundance patterns of CEMP stars and post-AGB stars in the Magellanic Clouds allows us to learn about the thermodynamic properties of possible i-process sites. In particular the Pb abundances may hold the key to solving this mystery because this is one element that is predicted to be significantly enhanced by the s process at low metallicities, in contrast to observations of post-AGB stars which only show low to moderate Pb enhancements. In this talk I will present the results of nuclear-network calculations of i-process nucleosynthesis in comparison to observations.

## Spatial distributions of different metallicity groups in red giant branch of dwarf spheroidal galaxies

Han, Sang-Il

The Ca-by photometry of Galactic three dwarf spheroidal galaxies (Draco, Sextans, and Canes Venatici I) obtained from Subaru/Suprime-Cam is presented to study spatial distributions of the red giant branch (RGB) stars according to the metallicity. Due to the sensitivity of the Ca filter to the metallicity, metal abundance of the redder RGB stars in the hk index [=(Ca-b)-(b-y)] are larger than that of the bluer RGB stars and the width of the RGB in the hk index is broader than other colors. We show that the metallicity is correlated with the hk index from the comparison with theoretical isochrones as well as the spectroscopic data in the literature. This suggests that this index can serve as an alternative metallicity indicator and allow us to study the structural feature of different metallicity groups of stars for the relatively larger sample compared to spectroscopy. We present the spatial structure of metal-rich and metal-poor RGB groups defined from the hk index and discuss chemo-structural complexities in the context of dwarf galaxy formation theories.

## Professional- Amateur Collaboration in the Scientific Observations of Total Solar Eclipses

Hanaoka, Yoichiro

Professional solar scientists and amateur astronomers in Japan have been energetically collaborated in the observation of the total solar eclipses in the last ten years. The collaboration has been producing scientific results, which have been published in scientific papers. The observation of the total eclipses has some advantages to let amateurs participate in as follows._x005F - The observation can be done with small telescopes._x005F - The multipoint observation can be realized. It helps to avoid the risk of the weather, and also enables to track the temporal variation of the corona_x005F - Wide range of amateurs, not only experienced ones but also beginners for the eclipse observation can contribute._x005F Therefore, the observation of the total eclipses is one of the most suitable targets to promote the participation of amateurs in scientific observations. Furthermore, because the astronomers from various nations gather to observe eclipses, it is expected that the more extensive collaboration is promoted by an international organization such as IAU. We will present our collaborative activities so far in our poster, and we would like to contribute to extending such activities.

## Fragmentation of Filamentary Cloud Permeated by Perpendicular Magnetic Field

Hanawa, Tomoyuki

We examine the linear stability of a filamentary cloud permeated by a perpendicular magnetic field._x005F The model cloud is assumed to have a Plummer-like profile and to be supported against the self gravity_x005F by turbulence. The effects of turbulence is taken into account by enhancing effective pressure_x005F of a low density gas. We derive the effective pressure as a function of the density from the condition of the hydrostatic balance. When the radial density profile is broader, i.e., the index is smaller, the model cloud is more unstable against radial collapse. When the magnetic field is mildly strong, the radial collapse is suppressed. If the displacement vanishes in the region very far from_x005F the cloud axis, the model cloud is stabilized completely by mildly strong magnetic field. _x005F If the rearrangement of the magnetic flux tubes is permitted, the model cloud is unstable even_x005F when the magnetic field is extremely strong. The stability depends on the outer boundary condition. _x005F The growth rate of the rearrangement mode is smaller for a lower index. We also discuss the case when the initial magnetic field is oblique to the cloud axis.

## Difference of the Gas Density Histograms in and out of spiral arms in Milky Way Galaxy

Handa, Toshihiro

Stars are formed from dense gas cores through the gravitational collapse. Before this stage less dense gas must be compressed and becomes denser. However, its mechanism is not clear. For example, Kennicutt-Schumidt law shows a correlation between amount of low density molecular gas traced by 12CO and star forming activity in a galactic scale, which means there should be some global relation between diffuse and dense gases. This is a way to understand “cosmic recycling of matter” completely. To address this issue directly we should investigate the density structure of the interstellar matter (ISM) in the galactic scale. Until now many investigators have focused on the spatial structure of ISM such as the core mass function. However, we make a statistical investigation, which ignores the local structure of ISM itself. This is another approach on the density structure. We call it “Gas Density Histogram (GDH)”, which is an observational counterpart of the probability density function (PDF) of the gas density of ISM if gas density structure is steady. We use “FOREST unbiased galactic imaging survey with Nobeyama 45-m telescope” (FUGIN), which is a large coverage survey in 12CO (1-0), 13CO (1-0), and C18O (1-0) with 15” resolution. Using the method of the kinetic distance estimation, we can also estimate the line-of-sight depth for each l-b-v voxel. Therefore, we can estimate the volume density of the voxel from the observed column density. The resultant GDHs show different shape from place to place in the Milky Way Galaxy; GDHs of the inter-arm regions show log-normal or similar to log-normal, but those in the spiral arm regions show log-normal with a bump in higher density or flat-top.

## Probing the Solar Interior with Computational Helioseismology

Hanson, Chris

Despite the numerous successes of helioseismology, our ability to effectively image the deep convective interior of the Sun is still lacking. This is due to both a lack of understanding of the observations (e.g., center-to-limb effect) and underdeveloped modelling (e.g., accurate sensitivity maps of wave travel times shifts due to flows). Understanding the sensitivity of the observables (travel times, ring fits, holograms, etc.) due to flows requires excellent models of acoustic wave propagation within the solar medium and of the various sources of noise. In this talk we will present a computational approach to modelling numerous flow structures in the solar interior (e.g. meridional flow and supergranulation), exploring the sensitivity of observables to different models. We show that these flow structures can be recovered from the observables (the inverse problem), by enforcing mass-conservation through classical inversion techniques and machine learning.

## A numerical investigation into the observable spin parameter

Harborne, Katherine

The observable spin parameter, λR, gives us a quantitative way to distinguish galaxy types according to how fast they rotate. This value is used quite frequently in many observational IFU studies. However, observations are always a 2-dimensional projection of a 3-dimensional object, which prompts the question – how well do the observed galaxy properties map to the true kinematic features?_x005F I have been developing a code to analyse numerical simulations of isolated galaxies, observing them as if using an integral field spectrograph, such as SAMI or MaNGA. The aim of this work is to quantify the levels of uncertainty in the spin parameter introduced by projection effects, beam smearing and measurement radius. As we have the original galaxy simulation, the modelled effects can be quantified for a range of galaxy structures by comparing the mock observables to the analytic form. Here, I will present the results of this work and introduce the code that has been developed, SimSpin.

## Census of Lya, [OIII]5007, Ha, and [CII]158um Line Emission with ~1000 Low-mass Lyman Alpha Emitters at z=4.9-7.0 Revealed with Subaru/Hyper-Suprime Cam Survey

Harikane, Yuichi

We investigate Lya, [OIII]5007, Ha, and [CII]158um emission from 1,125 low-mass galaxies (typically M*~10^8 Mo) at z=4.9-7.0, composed of 1,098 Lya emitters (LAEs) at z=4.9-7.0 identified by Subaru/Hyper Suprime-Cam (HSC) narrowband surveys and 29 galaxies at z=5.148-7.508 with deep ALMA [CII]158um data in the literature. Fluxes of strong rest-frame optical emission lines ([OIII] and Ha) are constrained by significant excesses found in the Spitzer 3.6 and 4.5um photometry. At z=4.9, we find that the rest-frame Ha equivalent width and the Lya escape fraction positively correlate with the rest-frame Lya equivalent width, EW^0_Lya. The typical ionizing photon production efficiency of LAEs is logxi_ion/[Hz erg^-1]~25.5, significantly (60-100%) higher than those of LBGs at a given UV magnitude, indicating the significant role of these low-mass galaxies in the cosmic reionization. At z=5.7-7.0, there exists an interesting turn-over trend that the [OIII]/Ha flux ratio increases in EW^0_Lya~0-30 A, and then decreases out to EW^0_Lya~130 A. We also identify a ~3sigma negative correlation between a [CII] luminosity to star-formation rate ratio (L_[CII]/SFR) and EW^0_Lya. We carefully investigate physical origins of these relations with stellar-synthesis and photoionization models, and find that a simple anti-correlation between EW^0_Lya and metallicity explains self-consistently all of the relations of Lya, Ha, [OIII]/Ha, and [CII] identified in our study, indicative of the detections of the very metal-poor (~0.04 Zo) low-mass galaxies with EW^0_Lya~200 A.

## Wikipedia for Astronomy: Improving a global resource for education and outreach

Harris, Hannah

Wikipedia is a common reference for students, scientists, the public, and anyone interested in astronomy. Due to its ubiquity when searching for information online, it is often the first resource a curious reader will encounter. Accurate astronomy-related content on Wikipedia enriches public understanding of astronomy, supports factual science journalism, and provides quality astronomy information in diverse languages. For astronomers, communicators, and educators, it matters what astronomical information is on Wikipedia, and whether or not that information is accurate and understandable. This poster summarizes the current state of astronomy on Wikipedia and how that information can be improved.

## Kepler K2: A Search for Very Red Stellar Objects

Hartig, Erich

Continuing the analysis of Long Period Variables (LPVs) observed as part of the Kepler K2 mission we show the latest results. We found that the 'Kepler K2 High Level Science Product' (K2HLSP) 'Self-Flat-Field' method (K2SFF or SFF) corrected the instrumental effects best. An iterative fitting method using sinusoidal functions was developed and evaluated.Furthermore, we present a strategy to properly constrain periods longer than the observational time basis using rms-error minimization. To check the results of this method, we applied it to a 33 d long dataset (1560 data points) of EP 202070273 (Kepler K2 Campaign 0) for which a ground based period of 730 d is available. The output from our method, 763 d, is in excellent agreement.From the Kepler K2 Campaign 2 we analysed a total of 41 targets data that are suspected or known LPVs. The 77.48 d of observations provided roughly 3500 data points. We searched for the SFF sinusoidal fit at the global rms-minimum and compared the periods with the available ASAS periods. In this way we defined the error range which could be applied to the rest of the targets.The preliminary results are presented in the poster.

## Dwarf Galaxies in the core of Coma Cluster

Hasan, Syed

Dwarf galaxies constitute 24% of the galaxies in the core of the Coma Cluster. In this talk,  I present the correlation between structural properties and morphology of galaxies in the central region of Coma Cluster for 221 objects within the apparent magnitude range m < 19.5. The data is taken from the HST/ACS Coma Cluster Treasury Survey and Source Extractor Catalogue compiled by Hammer et. al. 2010. For cluster membership we have used photometric redshifts of Michard et. al. 2008 & Edwards et. al.,2002 and spectroscopic redshifts of SDSS DR9 catalog. From the investigation of correlations of effective radius, Sersic index, absolute magnitude and bulge to total light ratio, we find that giants constitute 73%, Dwarf galaxies constitute 24% and the remaining 3% are Spirals+Irr+Ring. We found that multiple component fits are best for giants and the single Sersic fit is best for Dwarfs & Spiral galaxies. We shall try to explain why the single Sersic fit is best for Dwarfs and what kind of stellar orbits do they correspond to.

## A physically motivated dense-core extraction technique applied to Herschel/Planck observations

Hasenberger, Birgit

The evolution of dense cores in molecular clouds represents the earliest stage in the formation process of stars and planets. We are able to observe this stage by using multi-wavelength observations in the far-infrared and sub-mm range, which allow us to map nearby molecular cloud complexes in their entirety and resolve the core population embedded within them. However, the lack of a physically motivated definition of dense cores resulted in the development of a variety of algorithms designed to extract cores from observational data. In the most commonly used algorithms, core boundaries are based on the two-dimensional morphology of structures in the available maps, rendering the physical interpretation of results challenging. In addition, comparisons between studies of core samples are inherently problematic if different core extraction methods are employed.I will present a new method to define core boundaries observationally, based on the physical properties of the material in a molecular cloud. We model the flux distribution along the line of sight by taking into account the extent of structures on the plane of the sky. Subsequently, we can estimate the energy budget of cloud material in terms of its gravitational and thermal energy. The balance between these two contributions defines the boundaries of our cores. We illustrate the advantages and caveats associated with this approach by applying it to observations of the Pipe nebula by the Herschel and Planck satellites. We study in detail the derived core properties of this cloud, in particular the distribution of core masses.With this tool at hand, we are able to consistently define core samples in nearby molecular clouds, allowing us to compare core properties within individual clouds as well as between clouds. The development of a physically motivated core extraction algorithm thus represents an essential first step towards a deeper understanding of the processes involved in star formation.

## Dwarf Galaxies and Cluster Environments

Hashimoto, Yasuhiro

We report an investigation of the properties of dwarf galaxies (Mr < -15) inside 26 clusters at z=0.15-0.25, using optical images taken with 34' x 27' field-of-view Subaru Suprime-Cam and the X-ray data from the Chandra archive._x005F Our goal is to help understand the relationship between the dwarf and giant galaxies, and between the dwarfs and their host clusters to eventually address a question of the formation and co-evolution of galaxies and their environments._x005F Our results include:_x005F 1. Investigation of the dwarf galaxy density distribution is sensitive to the background galaxies and the choice of colour selection of galaxies._x005F 2. Under-estimating of the background galaxy counts tends to mimic a `flat' distribution of dwarf galaxies over cluster-centric distance. _x005F 3. Approximately 40 - 60% of faint galaxies always remain undetected by the detection algorithm near the center of clusters, even after carefully treating the halo or extra diffuse light created by bright galaxies. The number of 'undetected' faint galaxies varies significantly from cluster to cluster, and even from pointing to pointing. Meanwhile, the distribution of blue (more than 0.3 bluer than cluster red sequence V-I colour) dwarf galaxies extends more to the outside_x005F 4. Dwarf galaxies extend up to 2 Mpc from the center in most clusters. Meanwhile, the distribution of blue (more than 0.3 bluer than cluster red sequence V-I colour) dwarf galaxies extends more to the outside compared to red dwarf galaxies._x005F 5. For a given colour, the spatial distributions of dwarf galaxies and giant galaxies become similar, once the accurate background correction is applied. Namely, the major contribution to the difference in the radial distribution comes from the colour, rather than the size, of galaxies._x005F 6. Relative to the NFW profile, all of the galaxy populations are showing a deficit near the cluster core (r < 0.3 Mpc). The deviation is the most significant for blue dwarf galaxies.

## Space Weather on the Surface of Mars: Impact of the September 2017 Events

HASSLER, Donald M.

Although solar activity is declining as the Sun approaches solar minimum, a series of large solar storms occurred in September 2017 that impacted both Earth and Mars. This was the largest event seen on the surface of Mars since the landing of the Mars Science Laboratory (MSL) in 2012, and was also observed as GLE72 on Earth, making it the first event observed to produce a Ground Level Enhancement (GLE) on 2 planets at the same time! Due to the modulating effect of the Martian atmosphere and the magnetic cloud associated with the Coronal Mass Ejection (CME), the structure and intensity of the spectra observed at the surface are complex.  We present the observations of this event obtained with the Radiation Assessment Detector (RAD) on MSL and discuss the implications for our understanding of such events and for mitigating the risk of space radiation and space weather for future human exploration.

## Bridging the Gap of How One Feels about Large Facilities

Hayashi, Saeko

When you share common interest, you get friends. When you share common concerns, you become friends. When you sit together, you get better understandings. Even with people who have different views, we can work things out. That is what I believe, even when faced with strong oppositions against a proposal for a large facility to be built outside of my own country. And this is what I experienced – sitting in the same room, embrace the opportunity to face each other, I did find the overall concept is common._x005F Then how can we build common “ground”? The key is embedded in how we view the long -term future. Sometimes you encounter this argument, “not in my backyard” about the construction of big buildings or facilities. Then if the new project does not come to one’s neighborhood, that situation might lead to the loss of the livelihood there. I would like to discuss examples I witnessed which helped interactions between groups of opposite views. I do not have the desired outcome yet, but I believe the mutual understandings is one important key to make it come.

## The Star-Formation History of the Early Universe as Revealed by Blind Searches for Far-infrared Emission Lines

Hayatsu, Natsuki H.

Using blind line searches to understand the cosmic star-formation history is one of the strategies that will be pursued by next-generation millimetre/sub-millimetre single-dish telescopes which will have high sensitivity and mapping speed.  Before moving into such a new era, it is essential to develop a method to efficiently detect faint line-emitting sources whilst considering the completeness of source detection and contamination by false detections.  Furthermore, in order to propose robust strategies for blind line searching, it is necessary to know to what extent we can constrain the luminosity function using existing ALMA archival data.In this presentation, we report the current status of tests using a blind line-searching method and show preliminary results using ALMA archival data.  We discuss the detectability of line-emitting sources with various properties, e.g. peak flux, line width and spatial size, by injecting artificial sources into the ALMA data.  To be as realistic as possible, this is done in the visibility plane, and we also investigate the effect of non-Gaussian noise.  We compare the performance of the following three methods: (1) clump-finding and smoothing, (2) matched-filter analysis and (3) Bayesian analysis.We plan to apply our final results to various science cases for future observations, e.g. cross-checking the luminosity density using an intensity-mapping technique or estimating the redshift evolution of ionisation state or metallicity by combining with JWST or SPICA data. We plan to release our code as a CASA task.

## Galactic Simulations of r-process Elemental Abundances

Haynes, Chris

We present the results of chemodynamical simulations with the inclusion of four different neutron capture processes: magneto-rotational supernovae, neutron star mergers, neutrino driven winds and electron capture supernovae. We examine both simple isolated gas discs and cosmological zoom-in simulations of a Milky way-type galaxy and compare the [Eu/Fe] and [Eu/O] evolution with recent observations, including the HERMES-GALAH survey. We find that neither electron capture supernovae or neutrino driven winds are able to adequately produce neutron capture elements to match observations. Both neutron star mergers and magneto-rotational supernovae are able to produce the elements in sufficient quantities; additionally we find that the scatter in [Eu/Fe] at low metallicity ([Fe/H] < -1) and the [Eu/O] slope at high metallicity ([Fe/H] > -1) give an important constraint on the r-process sites. Using these we predict that neither neutron star mergers or magneto-rotational supernovae are able to explain the observed europium abundances separately and can better match observations with a significant contribution from both.

## Disentangling radio galaxy magnetism with the QUOCKA Survey

Heald, George

I will introduce the QUOCKA survey: QU Observations at Cm wavelength and Km baselines with the ATCA (Australia Telescope Compact Array). The aim of the QUOCKA survey is to provide a gold-standard set of broadband radio polarization spectra for active galactic nuclei (AGN) in the southern sky. QUOCKA will build on, and complement, the ASKAP POSSUM survey via targeted full-polarization imaging observations covering the 1-8 GHz range. The primary science goals are to: (i) characterise the internal magnetic field and plasma structure of radio lobes, jets, and their environments from exquisite broadband linear polarization spectra; and (ii) perform the first large-scale search for and characterisation of broadband circular polarization from radio galaxies. QUOCKA observations begin in mid-2018 with an initial sample of 250 radio galaxies selected from ASKAP Early Science fields. I will summarise the observational progress, demonstrate the data quality, and present initial results from the survey.

## Disentangling radio galaxy magnetism with the QUOCKA Survey

Heald, George

I will introduce the QUOCKA survey: QU Observations at Cm wavelength and Km baselines with the ATCA (Australia Telescope Compact Array). The aim of the QUOCKA survey is to provide a gold-standard set of broadband radio polarization spectra for active galactic nuclei (AGN) in the southern sky. QUOCKA will build on, and complement, the ASKAP POSSUM survey via targeted full-polarization imaging observations covering the 1-8 GHz range. The primary science goals are to: (i) characterise the internal magnetic field and plasma structure of radio lobes, jets, and their environments from exquisite broadband linear polarization spectra; and (ii) perform the first large-scale search for and characterisation of broadband circular polarization from radio galaxies. QUOCKA observations begin in mid-2018 with an initial sample of 250 radio galaxies selected from ASKAP Early Science fields. I will summarise the observational progress, demonstrate the data quality, and present initial results from the survey.

## IAU National Outreach Contact: Sri Lanka – Activities and Challenges

Heenatigala, Thilina

The IAU National Outreach Contacts (NOC) network was established in 2013 with the purpose of centralising global outreach efforts and to empower local representation. The IAU Office for Astronomy Outreach (OAO) acts as the central coordination point of the NOC network to support the projects at a national level.IAU NOC Sri Lanka is actively engaged in activities and spent time at the IAU OAO office at the National Observatory of Japan in Mitaka to strengthen the collaboration and to support projects. Like many nations, Sri Lanka has quite a few amateur and school based astronomical societies in several parts of the country. But currently there’s no research level astronomy or degrees at private or governmental institutions. However, there are currently about 10-15 professional astronomers from Sri Lanka working abroad and about 5 students pursuing astronomy for higher studies. In recent years, with the support of NOC, students could participate in IAU’s International School for Young Astronomers, International Space University, and other courses. While there’s a large interest in astronomy among public and students, there are quite a lot of challenges from traditional superstitious, astrology, and lack of options for higher studies in astronomy.This poster highlights the current astronomy activities of Sri Lanka, some of the major achievements and challenges the country face in further the astronomy education and research.

## Standardising Teacher Training with 10 Years of Lessons from Galileo Teacher Training Programme

Heenatigala, Thilina

The Galileo Teacher Training Programme was launched in 2009 as a Cornerstone project of the International Year of Astronomy 2009 (IYA2009). The core concept of the programme is to train teachers around the world and to better equip them with right resources and knowledge to use astronomy as a tool in the classroom.During the almost 10 years of the period, the GTTP has trained and certified 20, 000 teachers around the world, while the programme has reached a total of more than 50, 000 teachers. The host organisation of GTTP, the Núcleo Interactivo de Astronomia (NUCLIO) alone has trained and certified about 5, 000 teachers in Portugal, while reaching about 10, 000. GTTP has trained teachers in collaboration with European funded projects; Discover the COSMOS, Inspiring Science Education, Go-Lab, Space Awareness, among others bringing the latest trends, tools and evaluation in teacher training in astronomy education. The programme has also collaborated with major partner organisations such as Global Hands-on Universe, European Space Agency, European Science Education Academy and Leiden University to create interdisciplinary training events.Combining these lessons learnt, evaluation and experience from the past decade, the programme will build a competency profile for teacher training in astronomy to be used in IAU activities in training teachers, OAD funded projects, OAO network, and affiliated projects. The core competencies will include developing, implementing, organising, and evaluating of teaching STEAM subjects using astronomy as a tool. The new GTTP methodology will represent the 21st-century skills for teachers as well as produce the highest quality of content reviewed by experts in the field. The characteristics of the competency profile will align and complement the framework of IAU strategic plan 2020-2030.

Heesen, Volker

## Galactic winds in nearby galaxies traced with radio continuum observations

Heesen, Volker

Galactic winds driven by cosmic rays (CRs) have since long been suspected to be an important ingredient in the evolution of galaxies, however, they have been proven elusive to detect observationally. This is possibly now about to change with the advent of sensitive low-frequency observations such as with the Low-Frequency Array (LOFAR), allowing us to see CR electrons far away from star-formation sites. They can be combined with new broadband, high-frequency observations such as with the refurbished Very Large Array (VLA), in order to study spatially resolved radio continuum spectra at matched angular resolution and sensitivity. On the modelling side there has been progress as well, both with numerical 3D simulations incorporating CR transport as well as with 1D semi-analytical models of CR-driven winds and of pure CR advection and diffusion. Here, we present results from our survey of nearby late-type spiral edge-on galaxies using archival data from a wide range of radio interferometers and single-dish telescopes as well as new observations at 140-MHz with LOFAR and 1.5- and 6-GHz observations from the CHANG-ES (Continuum Halos in Nearby Galaxies – an EVLA Survey) survey to explore the vertical CR transport in radio haloes. Early results are promising, with two types of haloes emerging: either they can be described as diffusion dominated, with diffusion coefficients in fair agreement with the Milky Way value, or they are advection dominated, with advection speeds within a factor of two in agreement with the escape velocity near the galactic mid-plane. This raises the possibility that winds are common in star-forming galaxies; they are visible as radio haloes extending over the entire disc and are related to processes connected to star formation. More work needed to better understand the relationship between cosmic rays and magnetic fields with other halo constituents such as the warm neutral, warm ionised, and hot ionised medium.

Heesen, Volker

## 3C 294 revisited

Heidt, Jochen

3C 294 is a powerful FR II radio galaxy at z = 1.786 dominated by a Z-shaped structure with a relatively weak core at 6cm. The galaxy is associated with a large cloud of ionized gas aligned with the inner part of the radio structure. Due to its proximity to a bright 11th mag star it is an ideal target for observations with modern AO-systems. Previous AO-observations of 3C 294 have resolved this source in several subclumps perhaps in the process of merging. This is supported by an apparent overdensity of faint red galaxies in its vicinity. On the other hand, there are claims that 3C 294 consists of two active nuclei separated by a few kpc based on proper astrometry and acomparison with high-resolution X-ray data. Thus its evolutionary state and structure is complex and not yet fully understood. The findings described above are based on observations more than 15 years ago. Since then the AO-systems have become more advanced and the detectors more sensitive allowing observations of this sourcewith much better contrast and sensitivity than before. In this contribution we present and discuss a new data set of 3C 294 taken at the Large Binocular Telescope. In particular, we secured deep diffraction-limited JHK-images of 3C 294 accompanied by high-resolution (0.5" FWHM) JHK-images of its large-scale environment.The data set is complemented by deep optical spectra to search for signatures of a dual AGN.

## X-raying the clumpy stellar wind in the high-mass X-ray binary Cyg X-1

Hell, Natalie

Supermassive O/B-type stars exhibit strong stellar winds. Due to instabilities the hot wind material is prone to fragment into clumps of colder and denser material. The detailed structure of the wind and the clump morphology are still not well understood. In high-mass X-ray binaries (HMXBs), where these stars are paired with a compact object, the interaction with the compact object alters the wind structure further.Cyg X-1 is a persistent black hole HMXB with a supergiant O9.7Iab type star whose strong stellar wind is focused onto the black hole. The black hole is powered by accretion of the clumpy wind and the resulting continuum radiation is a perfect backlighter to X-ray and study the properties of the focused stellar wind. As the clumps pass our line of sight to the black hole, they cause excess absorption visible as dips in the observed X-ray lightcurves. The absorbing material imprints characteristic spectral signatures onto the continuum radiation from the black hole, depending on density, temperature, ion content (including a wide range of charge states), and velocity of the material. High-resolution spectroscopy enables us to use plasma diagnostics of Doppler shifts and line ratios of these signatures to determine the properties of the absorbing material. Analysing and comparing these high-resolution spectra at periods of different absorption levels, corresponding to different phases of the wind, thus allow us to put constraints on the size, morphology and distribution of the clumps. Here, we present our results of the clump characterstics derived from gratings observations of Cyg X-1 and discuss them in comparison to findings from other methods and to predictions of wind models.Work by LLNL was performed under the auspices of the U.S. DOE under Contract No. DE-AC52-07NA27344.

## The Evolution of Teacher Professional Development Workshops at McDonald Observatory

Hemenway, Mary K

Since 2001, McDonald Observatory has offered 1-10 Teacher Professional Development workshops on site in west Texas per year. Almost two thousand (elementary, middle, or high school) teachers attended workshops that provide hands-on/minds-on instruction in astronomy, related physical science, and earth science topics. Many activities are directly applicable in the teachers’ classrooms while others focus on improving teacher content knowledge. Most workshops include experience at the telescope, with the higher-level workshops using professional research telescopes and instrumentation. This paper will examine the development of the program and changes implemented to respond to teacher needs as science teachings standards have evolved through time. Recent evaluation results indicate that participants use the materials and activities within their classrooms, especially those that are easily implemented directly in the classroom, are low-cost, and hands-on. Teachers also identify the benefits and enjoyment of their unique interactions with professional astronomers and engineers with whom they interact as part of the program, and state that their confidence in teaching these scientific concepts is improved.

## Black Hole mass measurements with ALMA

We will present the results of our project to use molecular gas emission to measure or constrain the  mass of the supermassive black hole (SMBH) in a sample of nearby galaxies. Sample galaxies were selected to be those whose SMBHs are expected to have the largest angular  'sphere of influence' (SOI). We will present our high precision SMBH mass measurements in NGC 4751 and NGC 4945, and the implications of our (relatively highly resolved SOIs) results for SMBH constraints in galaxies whose SOIs are only partially resolved.

## The NIRSpec Microshutter Array Planning Tool

Henry, Alaina

The JWST NIRSpec multi-object spectroscopy (MOS) mode provides multiplexing 0.6–5.3 micron spectroscopy capabilities over a 3.6' × 3.4' field of view. This mode uses tiny configurable shutters in the micro-shutter assembly (MSA) to acquire dozens to hundreds of spectra of astronomical targets within a single exposure. In order to facilitate planning and execution of observations with custom configurations, our team has develop the MSA Planning Tool (MPT). This first-of-its-kind MOS design software works around the unique features of the MSA (e.g. stuck shutters), to optimize observations and reach the most high-priority science targets. In this poster, I will present a quick-start guide to using the MPT, and provide hands-on training to interested users.

## Raman-Scattered O VI 6825, 7082Å and C II 7023, 7053Å in the Symbiotic Nova RR Telescopii

Heo, Jeong-Eun

We present a high-resolution optical spectrum of the symbiotic nova RR Tel obtained with MIKE at Magellan-Claytelescope. RR Tel is a wide binary system of a hot white dwarf and a Mira with an orbital period of a few decades,where the white dwarf is accreting through gravitational capture of some fraction of material shed by the Mira.We find broad emission features at 6825, 7082, 7023, and 7053Å, which are formed through Raman scattering of far-UV O VI 1032, 1038, C II 1036 and 1037 with atomic hydrogen. Raman O VI 6825 and 7082 features exhibit clear double-peaked profiles indicative of an accretion flow with a characteristic speed ~40km/s. Raman C II features have a simple Gaussian profile of speed ~20km/s. We perform a profile analysis of the Raman O VI and C II features by assuming that O VI emission traces the accretion flow around the white dwarf with a representative scale of 1 AU whereas C II is formed in a much more extended region. A comparison of the restored fluxes of C~II 1036 and 1037 from Raman 7023 and 7053 and observed C~II 1335 an 1336 is consistent with the distance of RR~Tel $\sim 2 {\rm\ kpc}$ based on interstellar extinction of C~II.

## Prestellar Core Collisions

Herbst-Kiss, Gabor

I will present simulations of prestellar core collisions using the smoothed particle hydrodynamics code GANDALF. We focus on changes of the angular momentum, the internal energy, and the mass before and after the collision of prestellar cores in the interstellar medium. In the timeline of star formation, a molecular cloud has to lose 6-7 orders of magnitude of its initial specific angular momentum to the final formed protostar. This loss happens in distinct stages due to certain processes (e.g. magnetic braking, fragmentation and turbulence). The first entities formed out of fragmenting filaments are structures of several Jeans masses. These objects with small seperation could collide in regions of high core density. Also colliding clouds and filaments were already identified (e.g. in the Pipe Nebula) which favor collision processes. To study the effects of these collisions on the loss of angular momentum, we use Bonnor-Ebert and truncated Plummer spheres in a variety of initial states. Therefore, a set of simulations with various initial seperation distances, masses, impact parameters, alignments of rotation axis and turbulence will be run. We analyze the transport of angular momentum during the collision and loss due to linear movement and dissipation resulting from the collision. The numerical study of collision scenarios presents the conditions set to form stable, virially bound and unbound objects and the initiation for collapse of prestellar cores. The resulting v_lsr gradient of the 2D projected core, the oscillation patterns and dissipated material after the merge will help in the identification and interpretation of real observed cores. We will show preliminary results on our first targets of cores in the Pipe Nebula.

## Lyman Continuum Escape Channels in the HI Halo of SBS 0335-52E

Herenz, Edmund Christian

I will report on the discovery of ionised gas filaments in the circum-galactic halo of the extremely metal poor (Z/Zsun = 1/40) starburst galaxy SBS 0335-052E.  Due to its compactness and low-metallicity this galaxy is considered a good analogue of high-redshift star-forming galaxies.   Our observations with the MUSE integral field spectrograph reveal three ~10 kpc long and ~2 kpc wide filaments in Halpha and [OIII] down to surface-brightness levels of 10-19 erg/s/cm2/arcsec2.  VLA 21cm observations show that the compact starburst is embedded in a giant HI halo, that would naturally absorb all Lyman continuum emission from the  galaxies young stellar population.  However, a combined analysis of the MUSE and the VLA data suggests that the newly detected filaments likely penetrate fully through the neutral circum-galactic medium.   We therefore suggest that the  filaments, created by star-formation driven feedback, act as  Lyman continuum escape channels.   If such narrow channels are a general feature of high-z starbursts, their ionising radiation output would be highly anistropic and concentrated to small solid angles.  Accounting for this effect might be important when budgeting the ionising photon contribution from low-mass star-forming galaxies in reionising the universe.

## MUS(E)ings on the Lyman Alpha Emitter Luminosity Function at z~3-7

Herenz, Edmund Christian

One of the drivers for the construction of the MUSE Integral Field Spectrograph at ESOs VLT was to determine the Lyman Alpha Emitter Luminosity Function (LALF) at redshifts greater than 3. Here we present recent LALF results from MUSE surveys, with a focus on  the MUSE-Wide survey.  We demonstrate the construction of the selection function for this survey, and  we present different non-parametric, as well as parametric maximum-likelihood techniques to estimate the LALF.  In particular,  we find that by not taking the extended nature of Lyman alpha emitting galaxies into account, previous narrowband surveys understimated the number density of  fainter galaxies in their samples by factors of up to 3.  Moreover,  we show  evidence for an non-evolving observed LALF over the redshift range 3.1 < z < 6.7.  We conclude by highlighting the need for combined evaluation  of deep and ultra-deep MUSE observations with wide-field narrowband surveys in a homogenous statistical framework  for an accurate determination of the high-z LALF.

## Restarting activity in the nucleus of PBC J2333.9-2343

Hernandez-Garcia, Lorena

Under unification schemes, active galactic nuclei (AGN) can be explained by orientation effects. However, some sources show properties at different frequencies that led to incongruent classifications and cannot be explained by such unification scheme. This is the case of PBC J2333.9-2343; its optical spectrum is of a type 2 AGN but its X-ray spectrum does not show signs of absorption, and in the radio it has many features typical of a blazar but it is a giant radio galaxy. Using multiwavelength simultaneous data from XMM-Newton, San Pedro Mártir telescope and VLBA, we find that these classifications cannot be attributed to variability. We propose that PBC J2333.2343 is a blazar that has undergone a restarting activity episode in its nucleus. Interestingly, it has changed from being a radio galaxy to become a blazar, showing an exceptional change in the direction of the jet that, by chance, occurred in the plane of the sky. It also shows a change in the broad line region (BLR) clouds and increasing variability at all observed wavelengths and we have detected an outflow in its optical spectra.

## Chemical evolution models for Leo A and IC1613.

Hernández-Martínez, Liliana

We have developed one-zone chemical evolution models (CEM) for two dIrr galaxies, analysing their chemical evolution in a cosmological context. One of our main constraints in our chemical evolution models is the star formation rate obtained from very deep observations.  As part of our results, we are able to reproduce the metallic evolution estimated by observations. We have two main results: 1) from our CEM we can infer the mass assembly history (MAH) of each dIrr galaxy, and 2) we propose to include an outflow mainly driven by star formation, in order to reproduce the metallic evolution for Leo A while for IC 1613 the required outflow model must be more complex and ir would be explain in detail.

## Iron-nickel distribution on experimental barred olivine-like chondrules

Hernández-Reséndiz, Patricia

Barred olivine chondrules (BO) are fully melted chondrules and they constitute less than 10% of chondrules in ordinary chondrites (Jones 2012). We have prepared in our laboratory experimental BO chondrule-like melts with the purpose of studying the formation processes of type IA BO chondrules, as well as their physical and chemical characteristics. Samples were melted with the help of a 50W CO2 laser emitting in the infrared at a wavelength of 10.6µm inside a vacuum chamber at 0.76atm. We measured the distribution of relevant elements present in chondrules in our experimental samples (Fe, Mg, Ni and Mn), in order to understand the origin of chemical zoning and the evaporation rates of Fe and Ni. The values obtained for the Fe coefficient suggest that the crystallization occurred after a significant amount of evaporation of FeO (~50% of the total FeO content for starting material). We highlight Fe-Ni particles present in our analogs, with a similar composition as reported inside chondrules of Semarkona LL3.0 chondrite, and explore the hypothesis that Fe-Ni grains may have formed at the melting stage of chondrule formation. If this hypothesis is valid, Fe-Ni abundances in metal grains inside natural chondrules can yield information about pressure, evaporation and cooling rates during chondrule formation.

## Formation and Galactic Dynamic Evolution of Young Star Clusters

Hetem, Annibal

We present an analysis of a sample of clusters of young stars in order to investigate the inherent properties of clustering and dynamic evolution of stellar components. In previous works, we measured the parameter Q for a set of 25 clusters and the results were correlated with other properties of the spatial distributions determined through the King profile and show that almost half of these groups have a relation with the fractal dimension of their parental cloud. The statistical parameter Q was measured for the clusters and its correlations with the estimated fractal dimension for the projected near clouds are presented. There are also indications of the presence of substructures similar to those observed in the surrounding clouds. However, other clusters have a radial distribution that does not coincide with the structure of the clouds. These properties may lead to conclusions about the initial conditions of clusters formation (cold collapse or hot collapse), initial evolution (bound or not) and its expected galactic dynamic evolution (crossing time). These studies may give us information about the history of the influence of the Galaxy on clusters and how they were affected by their passage through their structures. In addition, present the application of new mathematical and numerical techniques with potentiality for use in models of filamentary structures.

## Exploring the dawn of black holes with the Lynx X-ray concept mission

Hickox, Ryan

In recent years, extragalactic surveys have made great strides in tracing the growth and evolution of black holes and their connections to galaxies and halos over most of cosmic history, from the local Universe to redshift 2 and beyond. However, the deepest, distant Universe remains relatively unexplored, and important questions remain about the emergence of “seed” black holes at z > 6, and their evolution over the first few Gyr up to the epoch of peak activity at z ~ 2, much of which may be "hidden" by obscuring material. I will present a brief overview of our current understanding of distant AGN, and will discuss prospects for the future with upcoming facilities such as JWST, WFIRST, Athena, and Lynx. I will focus particularly on how the high throughput and exceptional angular resolution of NASA's Lynx X-ray concept mission can revolutionize our understanding of the growth of black holes, their host galaxies, and environments the early Universe.  This work is supported in part by National Science Foundation CAREER award 1554584.

## Massive star evolution : mixing processes, rotationally-induced mass loss, and mass-luminosity relationships.

Higgins, Erin

Massive star evolution remains ambiguous with respect to key physical processes, yet advancements in theoretical modelling are essential in understanding the progenitors of black holes and neutron stars. As we continue searching for gravitational wave events like GW150914, it will be crucial to understand the evolutionary channels which led to such an event. We study the dominant processes such as mass loss, convective overshooting and rotation with the aim of constraining physical parameters qualitatively through MESA evolutionary models. Our results highlight the necessity of rotational mixing since observed intermediate level nitrogen enrichments are unachievable with only mass loss and convective overshooting, employed as mixing processes. We calibrate our stellar evolution models for a range of objects and compare them to previous grids of models (such as Brott et al. 2011, Ekstrom et al. 2012).

## Solo Dwarf Galaxy Survey: Exploring Isolated Dwarfs in the Local Group

Higgs, Clare

The Solo (Solitary Local) Dwarf Galaxy Survey is a volume limited sample of all nearby (< 3 Mpc) and isolated ( > 300 kpc from the Milky Way or M31) dwarfs, with wide-field g and i imaging. This survey uses resolved stellar populations to parameterize these low mass systems. Comparison to the well studied satellite dwarfs characterizes the evolutionary impact of a large galaxy in close proximity. The deep, wide field nature of this survey also lends itself to searching for substructure around these dwarfs, both globular clusters and possible faint satellites. I present a subset of the closest Solo dwarfs, all within the virial radius (approximately 1 Mpc) of the Milky Way. This sample has been characterized using consistent methods, despite the diversity in mass and size between these dwarfs. The analysis focuses on extended stellar structure and morphology, using resolved stellar populations. We then examine trends with star formation history, separation from a large host galaxy, and HI structure . This first subset emphasizes the unique challenges and advantages of this survey. In addition, I present a first look at a complete census of globular cluster candidates within these dwarfs. The Solo Survey provides detailed look at the extended structure of nearby dwarfs and aids in characterizing the evolution of galaxies in the faint limit.

## Toward understanding origin of gas in debris disks

Higuchi, Aya

Debris disks have optically thin dust components around main-sequence stars. We reduced ALMA archival data of the debris disk candidates and derived the dust and gas mass assuming the ISM abundance of CO/H2=10-4. From the result, we found a good correlation between dust mass and age of the central star: dust masses decrease with age of central stars. We expected the similar trend that gas masses decrease with the age, but found no trend between them. We thus concluded the ISM abundance is not a good assumption to derive H2 mass for debris disks. In addition, recently, we have firstly detected [C I] emissions in the gaseous debris disks of 49Ceti and ßPictoris with the ASTE. If C/CO ratio can be obtained by observations, there is a possibility to estimate the amount of H2 using the chemical reaction of CO.

## CHARACTERIZATION OF THE IMPACT OF AGN IN THE KINEMATICS OF A SAMPLE OF GALAXIES-CALIFA

Higuera G., Mario A.

Using techniques of integral field spectroscopy, it was made a study of the impact of AGN in its host galaxy, looking for kinematics of ionized gas of Ha, [OIII]5007 lines. There is evidence of a distortion in the velocity distribution field for objects with presence of an AGN. In order to develop the velocity field maps there was used a pipeline PIPE3D, which was elaborated by Sánchez, S.F. et al. 2016. There was found that in the central region of each working galaxy, there is evidence of higher kinematic speeds and higher dispersion speeds for the Ha and [OIII]5007 emission  lines, compared with the velocities that were observed in the control galaxies. It can confirm the activity in the nuclear region due to the presence of an AGN. It was found a disturbance in the velocity distribution field of the host galaxy, an alteration of the kinematic axis and of the velocity field distribution, which is different than expected for ideal disk galaxies. In contrast, the control galaxies showed properties of rather continuous and symmetric velocity distribution, as well as the presence of a kinematic axis. A difference in the distribution of kinematic speeds of Ha was observed in the circum-nuclear region of active galaxies. In a first approximation the object NGC 5443, presents higher kinematic speeds of Ha and [OIII]5007, in the central region compared to those that were evidenced in non-active galaxies, being very similar to the distributions found in the work galaxies NGC 5971 and NGC 2410. The object NGC 5443 does not have records in the literature as a LINER type object or as an active galaxy. It can be inferred first, that the IFS in a first approximation, is a potential tool that allows to demonstrate the presence of an AGN in places where previously such evidence could not be found; and secondly, that the maps of the ionized gas kinematics trace the possible existence of an AGN that may or may not be identified by other methods of study.

## The IAU 2000A Nutation Theory in a Binary-PCK Kernel

Hilton, James

The U.S. Nautical Almanac Office is constructing the IAU 2000A nutation theory ephemeris in a binary-PCK kernel for use in situations where speed of execution is critical. The nutation ephemeris will cover the time-span of the Jet Propulsion Laboratory's DE430 planetary ephemeris, JD 2287184.5-2688976.5 TDB (~1550.0-2650.0 CE). The method used in constructing this ephemeris also permits the evaluation of the instantaneous time rate of change of the nutation angles. Putting the theory in this format reduces the number of additions and multiplications required by about 2.75 orders of magnitudes each, and eliminates the need to evaluate any transcendental functions. The drawbacks of this representation are its limited time-span and the overhead of locating and reading the correct set of coefficients from the binary-PCK kernel. Extensive testing of numerous scenarios will be required to evaluate the true improvement in evaluation time. Currently, the conversion to a binary-PCK kernel is nearing completion. The project report at the General Assembly will include up-to-date information on testing this technique.

## Exploring the Radio Continuum vs. Star Formation Rate Relation in Nearby Dwarf Galaxies

Hindson, Luke

The source of the radio continuum (RC) emission from normal star forming galaxies is directly linked to massive stars and can be used as an indicator of the star formation rate (SFR). This is seen observationally in the RC-SFR relation. This relationship may provide a robust, unbiased, and perhaps most importantly an extinction free tool for characterising the SFR in both the Local Universe and at high redshift in upcoming radio surveys with instruments such as the VLA, LOFAR, and SKA. In an effort to calibrate the relationship and understand its physical origin we have undertaken a sensitive, multi wavelength, high-resolution study using the VLA of a sample of 40 nearby dwarf galaxies (a proxy for early type galaxies) taken from the LITTLE THINGS survey. By combining our VLA observations with ancillary data including H-alpha, 24um, and the FUV we separate the radio continuum emission into its thermal and non-thermal components and compare these to the SFR. We use these results to calibrate the RC-SFR relation on scales from 200 to 700 pc, explore the equipartition magnetic field properties of the galaxies, and the intrinsic scatter in the RC-SFR relation.

## The Structure of the Inner Circumstellar Shell in Miras

Hinkle, Kenneth

Stars undergo most of their mass loss on the AGB.  While the overall process is understood many details remain that need further study.  We report on spectra of near-infrared, low-excitation CO fundamental and first-overtone lines in three Miras.  The observations are in time series spanning up to two decades.  The temperature and velocity probed by the low-excitation CO lines are significantly different than that of the stellar photosphere measured by higher excitation lines.  The low-excitation CO region undergoes aperiodic variations.  The lines are shown to probe the structure of the circumstellar shell close to the star.  By drawing from the extensive literature on multi-frequency observations of Miras we show how the low-excitation CO region is connected to the structure of the circumstellar region and the mass loss process.

## Enrichment of heavy elements in chemo-dynamical simulations of dwarf galaxies

Hirai, Yutaka

Recent astronomical observations have shown that there are large star-to-star scatters in the abundances of r-process elements and increasing trend of Zn in extremely metal-poor stars. However, it is not yet clear how the early chemo-dynamical evolution of dwarf galaxies affects the abundances of heavy elements. Here we report that high-resolution N-body/smoothed particle hydrodynamics simulations of dwarf galaxies. We find that galaxies with star formation rates less than 0.001 solar masses per year reproduce the observed abundances of r-process elements assuming that neutron star mergers are the major astrophysical sites of r-process. On the other hand, r-process elements appear at a higher metallicity in galaxies with star formation rates greater than 0.01 solar masses per year. We also find that the ejecta from electron-capture supernovae contribute to stars with [Zn/Fe] > 0.5. The scatters of heavy elements mainly come from the inhomogeneity of the metals in the interstellar medium. We estimate that timescale of metal mixing is less than 40 Myr using heavy element abundances in metal-poor stars. This timescale is lower than that of typical dynamical times of dwarf galaxies. We also find that the r-process enhanced stars seen in the Milky Way halo are formed in halos with a size of ultra-faint dwarf galaxies by using our high-resolution cosmological zoom-in simulations. Our results demonstrate that the future observations of the abundances of heavy elements in extremely metal-poor stars using forthcoming facilities will be able to constrain the early chemo-dynamical evolution of the Local Group dwarf galaxies.

## The Lifecycle of Dust and Metals in Low-Abundance Galaxies

Hirschauer, Alec

I will discuss the recent discovery of the extremely metal-poor star-forming galaxy Leoncino (~2% solar), among our most promising early-Universe analogues to date, and whose discovery heralds a boom in finding additional similar low-metallicity specimens.  Studies of such nearby low-abundance galaxies reveal the importance of the effect of chemical composition on star formation and the lifecycle of dust and metals during the peak epoch of star formation in the Universe.  I discuss plans to study the lifecycle of dust and metals with JWST GTO observations of the low-abundance star-forming galaxy NGC 6822 and the extremely metal-deficient blue compact dwarf galaxy I Zw 18.  In preparation for these observations, I am investigating the dusty stellar populations in NGC 6822 including the dust-producing stars (e.g., asymptotic giant branch stars) and young stellar objects.

## The formation of supermassive binary black holes in galaxy mergers

Ho, Yu-Heng

Using N-body simulations, we've investigated the formation of supermassive binary black holes(BBH) under different impact parameters, i.e. BBHs with different initial angular momentum, we've traced the individual supermassive black hole(SMBH) at an initial distance of 300 kpc, to the stage when the BBH becomes hard, the time scale of different stages has been estimated, and the relation between the orbital evolution and the properties of the stellar cores are discussed, also, the transfer of the angular momentum between the galaxy and the BBH is studied, we find that certain merger geometries of the galaxies do affect the lifetime of the BBH significantly, the duration time of the individual SMBH from entering the core of the merged galaxy towards forming a hard binary can be as long as 1.5 Gyr. Furthermore, in traditional loss-cone theory, triaxial systems are generally believed to be efficient towards removing the angular momentum of the BBH so that the binary can be driven into coalescence at the hardening phase, we find that this might not be the case for the early stage of the binary formation while dynamical friction still plays the dominant role of subtracting the BBH orbital energy. We conclude that the geometry of the merger as well as the structure of the galactic angular momentum also plays an important role of determining the lifetime of the BBH, the situation might be more complicated if, for example, multiple mergers or larger mass ratio between the SMBHs are considered.

## New Insights in Interstellar Nanoparticles

Hoang, Thiem

Interstellar nanoparticles, including polycyclic aromatic hydrocarbons (PAHs), nanosilicates, and iron nanoparticles, are believed to play an important role in modern astrophysics. Mid-infrared emission from PAHs is widely used as a tracer of star formation activity. PAHs is also thought to be a leading carrier behind the long-standing mystery of Diffuse Interstellar Bands (DIBs). In this talk, I will discuss new insights into the crucial importance of interstellar nanoparticles. I will start with a review on anomalous microwave emission (AME) by rapidly spinning nanoparticles and the AME polarization, which is a critical challenge for constraining cosmic inflation via B-modes in cosmic microwave background (CMB) polarization. I will then present a new model of polarized emission from PAHs and discuss important implications for getting insight into the alignment physics of nanoparticles and for a potential new way of tracing magnetic fields via mid-IR polarimetry.

## Spectroscopy of Spatially Resolved Exoplanets with JWST NIRSpec

Hodapp, Klaus

The NIRCam science team will use part of their guaranteed observing time to image exoplanets with the coronagraph in NIRCam, obtain transit spectroscopy with the slit-less prism spectroscopic mode of NIRCam, and use NIRSpec for integral field (IFU) spectroscopy of exoplanets that are spatially resolved from their parent Star.This poster describes the latter of these observing projects. Our goal is to obtain spectra in the 3.0 - 5.0 µm range, where most moderately young exoplanets are expected to be brightest, with sufficient resolution (R=1000 and SNR (>30) to allow a detailed comparison with model atmospheres.In the 3 - 5 µm range, JWST is uniquely capable for these observations. We will use the NIRSpec spectrograph with its integral field unit (IFU) to preserve as much information as possible about the residual speckle pattern. The primary component will be outside of the IFU, but its speckle pattern will dominate the read noise out to several arc-seconds separation. We plan on observing at two telescope role angles to subtract out the primary component PSF. The wavefront stability and precision of pointing of JWST are essential for these observations.There are only a small number of suitable spatially separated exoplanets currently known. It is important that we observe several of these with JWST early in its operation, so that we establish the techniques and demonstrate feasibility.

## Revisiting Historical Novae

Hoffmann, Susanne

In our project we are studying historical reports of transient phenomena aiming at a catalogue of novae. Lists of historical nova candidates had been published before, for instance by Hsi 1957, Ho 1962, Clark & Stephenson 1976, Hasegawa 1980, Duerbeck 1986, Xu et al. 2000, and others – mostly collections of guest stars including much more phenomena. Our survey is a review and re-analysis of all those suggestions. A historically reported tailless "guest star" could in principle be a comet without visible tail, a nova, a supernova, a kilo- or macro-nova, or even a meteor._x005F By applying clear criteria to the different phenomena and by taking special care on transforming the old prosa text's information into modern coordinates for follow-up observations, we consider in particular those "guest stars" recorded with precise position and as having appeared for more than one night._x005F In our contribution, we review and discuss some suggestions of historical novae, such as "Nova Scorpius 1437" (Shara et al. 2017), CV BK Lyn as nova AD 101 (Patterson et al. 2013, Hertzog, 1986), and the guest star of AD 396 (Hertzog, 1986) regarding whether or not they fulfill genuine nova criteria and how well the position of the historical observation can be constrained._x005F _x005F

## Analysing and Visualising MUL.APIN – a witness of Babylonian astrometry

Hoffmann, Susanne

The compilation of MUL.APIN has been canonical for more than a millennium and dates back before 1000 BCE. The first of two tablets contains of astronomical data like lists of heliacal rising dates, simultaneous risings and settings as well as constellations crossing zenith (the so called ziqpu-asterisms). Thus, the very first section of the text might also be a list of asterism and it is, therefore, called a star catalogue. Nevertheless, the list does not contain a single number to describe the position of a constellation. For the few single stars mentioned the position is given relative to their constellation. However, we think, we had been able to reconstruct the depiction of the Babylonian sky chart by this part of the text – within huge margins of error.Since it is also possible to use the data of risings and settings in Mesopotamia to map the reconstructed Babylonian asterisms on the celestial sphere, we wish to present a virtual 3D-image of the Babylonian globe.This leads to a new hypothesis: Using a globe like this, it appears very intuitive to obtain the data written in the second to sixth section of the first tablet of the series. Up to now, there had been many speculation, computations and guesses, why all dates of risings are multiples of 5 and how to interpret the lists's order. If they are read from a globe, all this is an automatic product: Positioning the globe on a certain date, it is easy to read the asterisms above the eastern and western horizons as well as the asterism following below the eastern horizon in soandso many days. Hence, the usage of a globe to compile the lists of MUL.APIN might explain many aspects in an easy way.Therefore, in our contribution, we do not only want to suggest a fulldome-visualisation of Babylonian constellations for modern planetariums but also a historically brave hypothesis of a Babylonian globe and encourage archaeologists to dig for it.

## After 65 years dedicated to astrometric instrumentation, a Gaia successor is in sight

Høg, Erik

The astrometric foundation of astrophysics has been enormously improved by two ESA satellites that determined the positions, distances and motions of stars. I was fortunate to be at the right place and right time so that I could contribute towards various developments after beginning work as a student in 1953 at a new Danish meridian circle. These include the designs of:  a new method of astrometry by photon counting for the Hamburg meridian circle in 1960; a new design for the Hipparcos mission in 1975; the Tycho experiment for the Hipparcos satellite in 1981; direct-imaging on CCDs for the Gaia mission in 1992; and most recently, a Gaia successor in 2013 that should be launched in about twenty years. In April 2017 ESA approved our proposal (Hobbs et al. 2016, arXiv 1609.07325) to study a Gaia successor with infrared detecting capabilities. That proposal was one of three selected out of 26 submitted in response to ESA's call for new "Science Ideas" to be investigated for feasibility and technological developments. The study by ESA has resulted in the focal plane with NIR sensors shown on the poster at lower right.

## SOFA - Providing Standards via Software

Hohenkerk, Catherine

The Division A functional working group, Standards of Fundamental Astronomy (SOFA), continues its task of establishing and maintaining an accessible and authoritative set of algorithms and procedures that implement standard models used in fundamental astronomy.  This poster highlights the current software collection that SOFA makes freely available in thirteen different areas; astrometry, time, precession-nutation, to name but a few.   This will include the new routines that were added during the last triennium.

## Multiband study of AGB stars in clusters

Hojaev, Alisher S.

The interest to AGB population which consists of evolved cool luminous low- to intermediate mass stars (0.6-10 Ms) and exhibits the late phase of life of solar-type stars as well is still growing these years. In the one hand, increasing data stream from the modern facilities and instruments revealing new or clarifying known properties of AGB stars, in the other hand, enhancing computer capabilities allow to high-performance 3D modeling of physical conditions and phenomena connected with AGB stars. Especial importance of red giants observations in AGB and pre-AGB stars stages is in application of their group properties (particularly, TRGB and RCG) to the modeling of stellar systems, particularly open and globular clusters, for example, to estimate the age of the system. For this purpose we have carried out multiband photometry for the large sample of open clusters on 0.6-1.5 m class telescopes at Maidanak, Byurakan, Lulin observatories. The group parameters for clusters were determined and discussed. The continuation of observational study of AGB stars is planned. One of the new and perspective observational programs in research of open, globular clusters and other stellar systems is a intermediate and narrow band photometry within the frame of international all-sky survey of northern hemisphere. Further we intend to obtain spectral and deep photometric data using modern adaptive 4 m class telescope to be created in Uzbekistan and has been intended to install at Maidanak observatory well-known by excellent conditions for astronomical observations (large amount of clear sky, high quality and stability of atmosphere optics, etc) and advantageous location for time domain astrophysical research.

## H2 and HI clouds in dwarf galaxies

Hojaev, Alisher S.

Based on radio astronomy data available in special resources and using the data mining technology (aka, knowledge discovery in databases, KDD) the general catalog of extragalactic molecular and atomic hydrogen clouds and nebula was created and analyzed. Although the main part of such objects is located in spiral galaxies at different distances from the Milky Way Galaxy a few samples of dwarf galaxies also have such structural elements as well, according to the observational data. In accordance with the range of their masses and sizes as well as other physical parameters the observed clouds are of giant and hyper-giant molecular cloud class objects. The statistical and physical correlation analyses were made on clouds features and basic physical parameters. The results were compared with other types of galaxies where the molecular and atomic hydrogen clouds and nebula were ever observed. The gaseous clouds of both dwarf irregular galaxies and giant spirals are apparently located near the boundary of gravitational instability that promotes active star formation. The theoretical modeling of dynamical evolution of these galaxies as well as massive star formation in low [Fe/H] environment are also considered and discussed.

## Exo-environment in solar neighborhood: from molecular gas to protoplanet disks

Hojaev, Alisher S.

Relying on the data of complex general catalog we compiled using the KDD method (knowledge discovery in databases), the 3-D distribution and physical properties of molecular clouds in local galactic environments of the Sun were analyzed. We also combined a detailed database of the star formation indicators and young-star populations in the solar neighborhood, and protoplanetary accretion disk evidences around CTTS and WTTS were considered and discussed. The search and detailed study of exoplanets and protoplanets on 4 meter fully adaptive telescope with laser-guide-star technology which is creating to install at Maidanak astrophysical observatory (Uzbekistan) having the perfect seeing conditions as well as an appropriate geographical localization to support the time-series observations as well as other time domain astronomy features are included into scientific program of the telescope and discussed in report.

## Prospect science with modern 4 meter class telescopes

Hojaev, Alisher S.

According governmental initiatives to promote and enhance astronomical research in Uzbekistan, which do has deep roots and recognized achievements in ancient astronomy, the work has been started to create a 4-meter adaptive mirror telescope using the laser-guide-star wave-front correction technology. The telescope is intended to install at Maidanak astrophysical observatory well-known by perfect seeing conditions for astronomical observations (large amount of clear sky, high quality and stability of atmosphere optics, sharp FWHM of stellar image, etc.) as well as advantageous geographical location which makes it as a indispensable node for time domain astrophysical research. The international multi-messenger channels of observation are expected. The traditional for Maidanak observatory time-series observations are included into a preliminary scientific program of the telescope but they will be extended to much more deep level photometric and spectral data. The search and detailed study of exoplanets and protoplanets, exoplanet habitability issues, study of star formation in the Galaxy and in distant galaxies, optical identification and spectral survey of X-ray sources in galaxy clusters, transient phenomena such as gamma-ray bursts, supernovae, and compact mergers, especially optical and infrared afterglows of the gravitation waves emitters, are within the key multi-messenger sources. The necessary assistance from the IAU headquarter, its nodes and ELT community is described and discussed in the 4 meter telescope creation, its equipping with focal plane instrumentation and preparation of highly qualified astronomers who could be the local users for the advanced telescope. Possible synergy with other telescopes including that of extremely large class is considered.

## Essay on astronomy outreach issues

Hojaev, Alisher S.

Outreach and wide popularization of astronomy among broad community, cooperation of professional astronomy researchers with amateur astronomers and citizen-science projects in astronomy are really important in era of globalization and significant growth of scientific discoveries and extremely large data flow (Big-data) in all fields of astronomy. The draft overview is presented on astronomy science and outreach in Uzbekistan from ancient to now and further including the new trends (triune complex of the scientific park, boarding school and professional research institute for astronomy, astronomy and aerospace summer camps, mass-media, etc.). The ideas are proposed to increase the outreach issues of open astronomy for public.

## Toward new IAU Strategic Plan

Hojaev, Alisher S.

Coming closer to the completion of the first decadal (2010-2020) Strategic plan of the IAU on Astronomy for Development and preparing the new IAU Strategic Plan we should note the benevolent influence of IAU Office of Astronomy for Development (OAD) on convergence of astronomers and enhance their role in research, education and outreach. There are undoubted achievements, however, the OAD's role in promotion and supporting astronomy at regional and local level through international scientific and technological cooperation, the exchange of experts and assistance in the training of relevant specialists should be strengthened and enhanced. Until now, our colleagues of National Astronomical Observatories of Chinese Academy of Sciences (NAOC) together with astronomers of Ulugh Beg Astronomical Institute of Uzbek Academy of Sciences have renovated and modernized the 1 meter Zeiss telescope at Maidanak observatory (Uzbekistan) and we started deep halph-sky survey within international collaboration with NAOC, Xinjiang astronomical observatory (Chinese Academy of Sciences, China) and Steward observatory (University of Arizona, USA) in special SAGE intermediate- and narrow- band photometric system (developed by astronomers of NAOC). Recently, thanks to governmental efforts to promote and enhance astronomical research, which has deep ancient traditions and world-class achievements in Uzbekistan, a remarkable breakthrough in the development of astronomy and space sciences, education and their promotion is expected. A park of astronomy and aeronautics, an astronomical boarding school are being created, research has been started to create a 4-meter adaptive mirror telescope with laser correcting system. The necessary assistance and possible support from the OAD are described and discussed in the 4 meter telescope creation, the developing of the focal plane instrumentation and preparation of highly qualified astronomers who will be the local users for the advanced telescope.

## Spatial and Temporal Correlations in the Interstellar Medium

Hollins, James

We apply correlation analysis to random fields in numerical simulations of thesupernova-driven interstellar medium (ISM) with the magnetic field produced bydynamo action, and compare the properties of simulated radio observables withthe physical components in the model.We consider the cold, warm, and hot phases of the ISM separately; theanalysis mostly considers the warm gas, which occupies the bulk of thedomain.The correlation scales of random magnetic field, density, and velocityare distinct at all heights in the warm phase.The correlation time of the random velocity is comparable to the eddy turnovertime, although it may be shorter in regions with a higher starformation rate.The random magnetic field is anisotropic, with the standard deviations ofthe $y$- and $z$-components enhanced compared to the standard deviationof the $x$-component.The anisotropy is attributed to the global velocity shear from galacticdifferential rotation, and locally inhomogeneous outflow to the galactichalo.The correlation length of Faraday depth along the is greater than thecorrelation lengths of both electron density and vertical magnetic field.Such comparisons may be sensitive to the orientation of the line of sight.Uncertainties of the structure functions of synchrotron intensity rapidlyincrease with the scale. This feature is hidden in power spectrumanalysis, which can undermine the usefulness of power spectra fordetailed studies of interstellar turbulence.

## Building a Radio Astronomy Community

Hollow, Robert

Universities around the world are looking for programs to differentiate themselves from others and to equip their students for the challenges presented by new technologies and facilities. With the advent of new radio telescopes such as the Square Kilometre Array and FAST and the massive data sets such facilities will produce opportunities to expose, engage and train students are becoming important. In response to this need and building on the success of the innovative PULSE@Parkes education program for high school students CSIRO Astronomy and Space Science in Australia have been developing a new program; OPTIMUS.OPTIMUS (Observing with Parkes, Training and Introduction, Module for University Science) is a flexible package providing undergraduate and postgraduate students a hands-on introduction to radio astronomy observational techniques and data analysis, using pulsars initially as the context. It includes background educational material, tutorials, a virtual machine to allow students to install a complete package of relevant software tools, access to data and telescope time on the 64m Parkes radio telescope plus support and observer training. Initial topics for the program include pulsar timing and the search for gravitational waves, but will in time incorporate other topics within astronomy and astrophysics.We outline the approach taken in developing the program and describe some of the tools produced. Various ways in which users can engage with the program are identified and we discuss how the program has evolved in response to extensive engagement with potential stakeholders around the world. The program provides a model for other institutions to provide effective training and for them to partner and build a global community.

## Rotating disks around M-type AGB stars

homan, ward

High-resolution observations of the circumstellar environments (CSE) of AGB stars reveals that companion-induced morphologies are common. High mass-loss rate C-rich winds occasionally exhibit convincing spirals, whereas O-rich environments seem to be less morphologically well-defined. We present a study on the morphology of the CSE of the M-type AGB star EP Aquarii, observed with ALMA (cycle 4). The data reveals a complex, nearly face-on equatorial density enhancement (EDE), enclosed by a bi-conical outflow. The EDE manifests primarily as a spiral, making this the first convincing detection of a spiral in an O-rich environment. The molecular emission also shows other peculiarities like rotation, potential mass-transfer and voids, all which suggest that a companion may be present. We deduce the position angle and inclination of the symmetry axis of the system, and conclude that the observable constaints favour the hypothesis that the EDE is dominated by a tangential velocity field, as opposed to a radial one. In addition, we also present recent findings of the CSE of R Doradus. Preliminary observations with ALMA (cycle 2) at coarse spatial resolution reveal that the innermost regions exhibits a spatial offset between the red and blue shifted emission for most observed molecules. We crudely model the highly compact 28SiO emission and show that it can be explained by a tilted rotating disk, with a tangential velocity governed by angular momentum conservation, and a small outward velocity field. Both EP Aqr and R Dor are semiregular variable stars. In combination with the recent observations and modelling results of the compact, edge-on, differentially rotating disk surrounding the nearby semiregular AGB star L2 Puppis, the increasing observational sample is revealing a potential relation between the pulsational classification of M-type AGB stars and their circumstellar morphology.

## Chemical evolution model to derive metallicity distributions for each stellar population

Homma, Hidetomo

I have constructed a new chemical evolution model for dwarf galaxies and compares its results with the observed chemical properties of red giant branch stars (RGBs) and RR Lyrae (RRL) stars of Sculptor and Fornax dwarf spheroidal galaxies (dSphs). The detailed chemical abundances of RGBs of nearby dwarf galaxies have been measured by spectroscopic observations. Moreover, the metallicity distributions of RRL stars are estimated from the theoretical Period-Luminosity relations in literature and it is found that the mean metallicity of RRL stars are lower than that of RGBs. In order to investigate the metallicity distributions of RGBs and RRL stars, the chemical evolution model of this study adopts the Padova stellar evolution tracks and derives the metallicity distributions of RGBs and RRL stars, respectively. Moreover, in order to derive the consistent chemical evolution with the observed color magnitude diagrams, the model adopts the star formation histories estimated from the color magnitude diagrams. The resultant chemical evolution models represent the observed metallicity distributions of RGBs in Sculptor and Fornax dSphs, respectively. However, the mean metallicity of RRL stars of the model of Sculptor dSph is lower than that of the previous work. Since the metallicity of RRL stars estimated from the theoretical Period-Luminosity relations depends on the distance modulus, it is found that the distance modulus of Sculptor dSph are larger than that of the previous work in order to represent the metallicity distributions of RGBs and RRL stars, simultaneously. The distance modulus of Sculptor and Fornax dSph derived from the chemical evolution models are $19.67 ¥pm 0.08$ and $20.81 ¥pm 0.13$, respectively. These values are consistent with the other previous works.

## MICHI: a Thermal-Infrared Instrument for the TMT : Four Key Science Drivers

Honda, Mitsuhiko

With the imminent launch of the JWST, the field of thermal-IR astronomy will enjoy a revolution. It is easy to imagine that all areas of IR astronomy will be greatly advanced, but perhaps impossible to conceive of the new vistas that will be opened. To allow both follow-up JWST observations and a continuance of work started on the ground-based 8m’s, we continue to plan the science cases and instrument design for a thermal-IR imager and spectrometer for early operation on the TMT. While JWST will have exceptional sensitivity over a wide field of view, TMT will offer superior spatial and spectral resolution, key to unraveling fundamental questions in nearly every field of astrophysics.We present our key science cases and the instrumentation plans, harnessing expertise across the TMT partnership. This instrument was proposed by the MICHI team as a second-generation instrument in the upcoming call for proposals.

## Gemini Observations of Two Candidate Planetary Nebulae toward the Galactic Center

Hong, Jihye

We present high-resolution near-infrared (IR) spectra of two candidate planetary nebulae (PNe) that were serendipitously found toward the Galactic center (GC). Our spectra obtained using GNIRS on Gemini North reveal strong Br ? and He I recombination lines. In one of the targets, we confidently detect Pa ß and Pa ? emissions. Based on Br ? and Pa ß lines, we estimate a foreground extinction Av ~ 20 mag for SSTGC 588220 and Av > 28 mag for SSTGC 580183. Given the large foreground extinction toward the GC, our extinction estimates plausibly indicate that they are located at the GC distance. Along with the presence of high excitation emission lines such as [S IV], [Ne III], [Ne V], and [O IV] detected in the mid-IR spectra from the Spitzer Space Telescope, and the extended emission in the Pa a narrow-band image from the Hubble Space Telescope, our observations suggest that they are the first spectroscopically confirmed PNe in the GC.

Horellou, Cathy

## Reliable detection and characterization of low-frequency polarized sources in the LOFAR M51 field

Horellou, Cathy

The new generation of broad-band radio continuum surveys will provide large data sets with polarization information. New algorithms need to be developed to extract reliable catalogs of linearly polarized sources that can be used to characterize those sources and produce a dense rotation measure (RM) grid to probe magneto-ionized structures along the line of sight via Faraday rotation.We have developed a computationally efficient and rigorously defined source-finding algorithm for linearly polarized sources.We used the calibrated data set from the LOw Frequency ARray (LOFAR) at 150 MHz centered on the nearby galaxy M51 to search for polarized background sources. We cataloged about 3000 continuum sources within 2.5 degrees of the center of M51. We made Stokes Q and U images centred on each source brighter than 100 mJy in total intensity and used RM synthesis to create Faraday cubes. For each source, the noise distribution function was determined; the peaks in polarized intensity in the Faraday spectrum were identified and the p-value of each source was calculated. Finally, the False Discovery Rate method was applied to the list of p-values to produce a list of polarized sources and quantify the reliability of the detections.  Of the 201 sources that were searched for polarization, six polarized sources were detected confidently. This corresponds to a number density of one polarized source per 3.3 square degrees, or 0.3 source per square degree. Increasing the false discovery rate to 50 percent yields 19 sources. A majority of the sources have a morphology that is indicative of them being double-lobed radio galaxies, and the ones with literature redshift measurements have 0.5<z<1.0.we find="" that="" this="" method="" is="" effective="" in="" identifying="" polarized="" sources. in="" the="" future,="" we="" intend="" to="" develop="" it="" further="" and="" apply="" larger="" data="" sets="" such="" as="" lofar="" two-meter="" survey="" of="" whole="" northern="" sky,="" lotss,="" ongoing="" deep="" observations="" goods-north="" field.<="" p="">
</z&lt;1.0.we&gt;</p>

## Variability in Post-AGB Stars: Pulsation and Binarity in Proto-Planetary Nebulae

Hrivnak, Bruce

We have intensely monitored photometric variability in proto-planetary nebulae (PPNe) over the past 25 years and radial velocity variability over the past ten years.  Pulsational variability has been obvious, in both the light and velocity, although the resulting curves are complex, with multiple periods and varying amplitudes.  Nevertheless, consistent patterns have emerged that give insight into the structure and evolution of the stars.  Observed periods range from 25 to 160 days, and the periods and amplitudes reveal evolutionary trends.  Evidence for binarity is more elusive, with no clear evidence emerging from these long-term radial velocity or light curves. We will present our observational results to date for approximately 30 PPNe, and discuss these results, including the search for period changes that might help constrain post-AGB evolutionary timescales.

## The Role of the Magnetic Field in the Molecular Inflow in the Central 10 pc of the Galactic Center - Implications From 850 micron Polarization Data

Hsieh, Pei-Ying

Utilizing James Clark Maxwell Telescope (JCMT) 850 micron  dust polarization data, weinvestigate the configuration of the magnetic (B-) field in the circumnuclear disk (CND) of the Galactic Center (GC).  Overall on a large scale, the B-field shows a clear predominantly toroidal morphology in the 2-pc ring rotating with respect to supermassive black hole SgrA*. In general, the observed B-field morphology is well described by a self-similar axisymmetric disk model where the radial infall velocity is one quarter of the rotational velocity. A detailed comparison with higher-resolution interferometric maps from the Submillimeter Array (SMA) further reveals that the B-field aligns with the neutral gas streamers where they are connecting to the CND.  Moreover, the innermost observed B-field structure also appears to trace and align with  the ionized mini-spirals located inside the CND.  This suggests that there might be one underlying B-field structure that is connecting the CND with its streamers and the inner mini-spirals. An estimate of beta_Plasma~0.02-0.04 -- based on the global B-field morphology that constrains  the azimuthal-to-vertical field strength ratio to be around 40 combined with a measurement of the azimuthal velocity -- indicates that the B-field appears dynamically significant towards the CND and also onwards to the inner mini-spirals.

## The Fossil Nuclear Outflow in the Central 30 pc of the Galactic Center

Hsieh, Pei-Ying

In Hsieh+ (2015, 2016, ApJ), we report a new 1 pc (30?) resolution CS(J=2-1) line map of the central 30 pc of the Galactic center (GC), made with the Nobeyama 45 m telescope. We revisit our previous study of an extraplanar feature called the polar arc (PA), which is a molecular cloud located above SgrA*, with a velocity gradient perpendicular to the galactic plane. We find that the PA can be traced back to the galactic disk. This provides clues to the launching point of the PA, roughly 6x10^6 years ago. Implications of the dynamical timescale of the PA might be related to the Galactic center lobe at parsec scale. Our results suggest that, in the central 30 pc of the GC, the feedback from past explosions could alter the orbital path of molecular gas down to the central tenth of a parsec. In the follow-up work of our new CS(J=2-1) map, we also find that, near systemic velocity, the molecular gas shows an extraplanar hourglass-shaped feature (HG-feature) with a size of ~13 pc. The latitude-velocity diagrams show that the eastern edge of the HG-feature is associated with an expanding bubble B1, ~7 pc away from SgrA*. The dynamical timescale of this bubble is ~3x10^5 years. This bubble is interacting with the 50 km/s cloud. Part of the molecular gas from the 50 km/s cloud was swept away by the bubble to b=-0.2 degree (27 pc from SgrA*). The western edge of the HG-feature seems to be molecular gas entrained from the 20 km/s cloud toward the north of the galactic disk. Our results suggest a fossil explosion in the central 3 0 pc of the GC, a few 10^5 years ago.

## Molecular Gas Feeding the Circumnuclear Disk of the Galactic Center

Hsieh, Pei-Ying

The interaction between a supermassive black hole (SMBH) and the surrounding material is of primary importance in modern astrophysics. The detection of the molecular 2 pc circumnuclear disk (CND) immediately around the Milky Way SMBH, SgrA*, provides a unique opportunity to study SMBH accretion at subparsec scales. Our new wide-field CS(J = 2 - 1) map toward the Galactic center (GC) reveals multiple dense molecular streamers that originated from the ambient clouds 20 pc further out, and that are connected to the central 2 pc of the CND. These dense gas streamers appear to carry gas directly toward the nuclear region and might be captured by the central potential. Our phase-plot analysis indicates that these streamers show a signature of rotation and inward radial motion with progressively higher velocities as the gas approaches the CND and finally ends up corotating with the CND. Our results might suggest a possible mechanism of gas feeding the CND from 20 pc around 2 pc in the GC. In this paper, we discuss the morphology and the kinematics of these streamers. As the nearest observable Galactic nucleus, this feeding process may have implications for understanding the processes in extragalactic nuclei. The results were published in the astrophysical journal (2017, ApJ, 847, 3).

## NOC activities at Myanmar

Htun, Boothee Thaik

The poster present the NOC acitivites at Myanmar

## A Thick Atmosphere on Super-Earth 55 Cancri e

Hu, Renyu

One of the primary questions when characterizing Earth-sized and super-Earth-sized exoplanets is whether they have a substantial atmosphere like Earth and Venus, or a bare-rock surface that may come with a tenuous atmosphere like Mercury. Phase curves of the planets in thermal emission provide clues to this question, because a substantial atmosphere would transport heat more efficiently than a bare-rock surface. Analyzing phase curve photometric data around secondary eclipse has previously been used to study energy transport in the atmospheres of hot Jupiters. Here we use phase curve, Spitzer time-series photometry to study the thermal emission properties of the super-Earth exoplanet 55 Cancri e. We utilize a previously developed semi-analytical framework to fit a physical model to infrared photometric data of host star 55 Cancri from the Spitzer telescope IRAC 2 band at 4.5 µm. The model uses various parameters of planetary properties including Bond albedo, heat redistribution efficiency (i.e., the ratio between the radiative timescale and advective timescale of the photosphere), and atmospheric greenhouse factor. The phase curve of 55 Cancri e is dominated by thermal emission with an eastward-shifted hot spot located on the planet surface. We determine the heat redistribution efficiency to be ~1.47, which implies that the advective timescale is on the same order as the radiative timescale. This requirement from the phase curve cannot be met by the bare-rock planet scenario, because heat transport by currents of molten lava would be too slow. The phase curve thus favors the scenario with a substantial atmosphere. Our constraints on the heat redistribution efficiency translate to a photosphere pressure of ~1.4 bar. The Spitzer IRAC 2 band is thus a window into the deep atmosphere of the planet 55 Cancri e.

## A formation mechanism of 4179 Toutatis-like elongated contact binary configuration

Hu, Shoucun

4179 Toutatis is a near-Earth asteroid with a bifurcated shape and an extremely slow tumbling rotation. The measurements from previous radar models and optical images acquired by Chang’e-2 spacecraft show that Toutatis has an elongated contact binary configuration, composed of two lobes (body and head), with the contact point located along the body’s long axis. We speculate that such configuration may have resulted from a low-speed impact between two components. In this work, we have performed a series of numerical simulations and further compared the results with the images captured by Chang’e-2, to examine the mechanism and better understand the formation of Toutatis. Herein we propose an scenario that an assumed separated binary precursor could undergo a close encounter with Earth, leading to an impact between the primary and secondary, and the elongation of the asteroid is caused by Earth’s tide. The precursor is assumed to be a doubly synchronous binary with a semi-major axis of 4 Rp (radius of primary) and two components are represented as spherical cohesionless self-gravitating granular aggregates. The mutual orbits are simulated in a Monte Carlo routine to provide appropriate parameters for our N-body simulations of impact and tidal distortion due to Earth. We employ the numerical package pkdgrav with a soft-sphere discrete element method (SSDEM) to explore the entire scenarios. The results show that contact binary configurations are natural outcomes under this scenario as long as using proper initial conditions, whereas the shape of the primary is almost not affected by the low-speed impact of the secondary. However, our simulations provide an elongated contact binary configuration best-matching to the shape of Toutatis at an approaching distance rp = 1.4 ~ 1.5 Re (Earth radius), indicative of a likely formation scenario for configurations of Toutatis-like elongated contact binaries.

## White Light Flare Activities of Eclipsing Binary Systems in Kepler Field

Huang, Li-Ching

From 2009 to 2013, the Kepler space telescope obtained high-precision light curves of about 160,000 stars in a 115-square-degree field near Cygnus and Lyra. Among them, about 2800 eclipsing binary (EB) system were identified. The Kepler data are very useful in the study of large stellar flares that usually last half hour to 3 hours because of the availability of long-term light curves at 30-min cadence. Gao et al. (2016) found superflare events on 234 EBs. The primary stars of 66 of these Kepler EBs are G-type (Teff ~ 5340K-6040K), 69 are K-type (Teff ~ 3880K-5340K) and 7 are M-type (Teff ~ 2450K-3880K). It is interesting to note that 72.7% of the G-type EBs are detached Algol systems, 63.8 % of the K-type EBs are Algols, and for the M-type EBs, 100% are Algols. The EB light curves can be used to make a first estimate on the temperature ratios of the primary and secondary components from which their physical properties (i.e., radii and masses) can be derived according to stellar models. This method should be more accurate for the detached Algol systems. In this work, some preliminary results on the temperature ratio (T1/T2), radius radio (R1/R2) and mass ratio (q=m1/m2) of the 7 M-type EBs are discussed with a comparison to their corresponding flare activities.

## On the origin of supergiant fast X-ray transients

Hubrig, Swetlana

A fraction of high-mass X-ray binaries are supergiant fast X-ray transients.These systems have on average low X-ray luminosities, but display short flaresduring which their X-ray luminosity rises by a few orders of magnitude. Theleading model for the physics governing this X-ray behaviour suggests that thewinds of the donor OB supergiants are magnetized. In agreement with this model,the first spectropolarimetric observations of the SFXT IGR J11215-5952 using theESO FORS2 instrument at the VLT indicate the presence of a kG longitudinalmagnetic field. Based on these results, it seems possible that the keydifference between supergiant fast X-ray transients and other high-mass X-raybinaries are the properties of the supergiant's stellar wind and the physics ofthe wind's interaction with the neutron star magnetosphere.

## Studying the presence of magnetic fields in a sample of high-mass X-ray binaries

Hubrig, Swetlana

Previous circular polarization observations obtained with the ESO FORS1instrument at the VLT in 2007-2008 revealed the presence of a weak longitudinalmagnetic field on the surface of the optical component of the X-ray binaryCyg X-1, which contains a black hole and an O9.7Iab supergiant on a 5.6d orbit.In our poster we report on recently acquired FORS2 spectropolarimetricobservations of Cyg X-1 along with measurements of four additional high-massX-ray binaries.

## Magnetic massive stars in star forming regions

Hubrig, Swetlana

One idea for the origin of magnetic fields in massive stars suggests that themagnetic field is the fossil remnant of the Galactic ISM magnetic field,amplified during the collapse of the magnetised gas cloud. A search for thepresence of magnetic fields in massive stars located in active sites of starformation led to the detection of rather strong magnetic fields in a few youngstars. Future spectropolarimetric observations are urgently needed to obtaininsights into the mechanisms that drive the generation of kG magnetic fieldsduring high-mass star formation.

## An abundance analysis of AK Sco, a Herbig Ae SB2 system with a magnetic component

Hubrig, Swetlana

AK Sco is an SB2 system formed by two nearly identical Herbig Ae stars, withT_eff = 6500 K and log g = 4.5, surrounded by a circumbinary disk. This activelyaccreting system is of special interest among the pre-main-sequence binariesbecause of its prominent ultraviolet excess and the high eccentricity of itsorbit. Moreover, recent spectropolarimetric observations using HARPSpol indicatethe presence of a weak magnetic field in the secondary component. An abundanceanalysis of both components has shown that all elements have a solar abundancein the two stars, except for Li and Ba. These elements are enhanced by 2.2 and0.5 dex, respectively, in the A component and by 2.4 and 0.5 dex, respectively,in the B component.

## ALMA Observations of Polarization from Dust Scattering in the IM Lup Protoplanetary Disk

Hull, Chat

We present 870 µm ALMA observations of polarized dust emission toward the Class II protoplanetary disk IM Lup. We find that the orientation of the polarized emission is along the minor axis of the disk, and that the value of the polarization fraction increases steadily toward the center of the disk, reaching a peak value of ~1.1%. All of these characteristics are consistent with models of self-scattering of submillimeter-wave emission from an optically thin inclined disk. The distribution of the polarization position angles across the IM Lup disk reveals that while the average orientation is along the minor axis, the polarization orientations show a significant spread in angles; this can also be explained by models of pure scattering. We compare the polarization with that of the Class I/II source HL Tau. A comparison of cuts of the polarization fraction across the major and minor axes of both sources reveals that IM Lup has a substantially higher polarization fraction than HL Tau toward the center of the disk. This enhanced polarization fraction could be due a number of factors, including scattering by larger dust grains in the more evolved IM Lup disk. However, our models yield similar maximum grain sizes for both HL Tau and IM Lup: on the order of 70 µm in both cases. This reveals continued tension between grain-size estimates from scattering models and from models of the dust emission spectrum, which find that the bulk of the (unpolarized) emission in disks is most likely due to millimeter (or even centimeter) sized grains.

## Digital Archives as an Outreach Resource: The Role of the Observatory Librarian

Hunt, Sharon

Digital archives are an increasingly important resource for astronomy outreach in this digital age. They allow for the preservation and wide dissemination of the information found in images and documents and serve as an important knowledge repository for outreach professionals, research astronomers, and the public.Observatory librarians can play an important role in outreach activities through the creation and maintenance of these archives. To be useful, information must be organized, described, and made accessible. As specialists in the organization and retrieval of information, librarians offer many skills: familiarity with organizational schemes; practice describing materials through metadata, finding aids, and indexes; proficiency in assessing the needs of diverse communities; an understanding of individuals’ information-searching behaviors; and the capability to design effective user interfaces to databases.The National Optical Astronomy Observatory (NOAO) has a large collection of historical materials—reports, newsletters, photographs, films, correspondence, brochures, videos, guides—illuminating our nearly 60-year-long history and our programs. The observatory librarian in conjunction with outreach personnel is digitizing and organizing these visual and textual materials into digital archives accessible through our website. This digital archives project will enhance access to our informational materials and assist us in extending our outreach activities to diverse communities through digital means.

## VLBA Imaging of ICRF 3 Sources

Hunt, Lucas

We present results from a Very Long Baseline Array (VLBA) campaign imaging sources used in the third realization of the International Celestial Reference Frame (ICRF 3). Imaging these sources allows us to determine spectral index, peak flux density, compactness and source structure index. This information is crucial to understanding source structure and variability which better allows us to determine if a source is suitable for inclusion in the ICRF and suitability as a phase reference calibrator.

## The Evolution of Radio AGN in XXL-S

Huynh, Minh

The XXL is the largest survey ever with the XMM-Newton X-Ray telescope, comprising 6.9 MS spread over two 25 sq deg fields, the XXL-N and XXL-S. The main goals of the XXL project are to probe cosmology using galaxy clusters and to study galaxy evolution with a large sample of AGN. As part of the ongoing multiwavelength followup to achieve these science goals, radio observations at 2.1 GHz were obtained on the Australia Telescope Compact Array covering the full 25 sq deg of the southern field, XXL-S, reaching an rms noise of ~40 microJy with a resolution of ~5 arcsec. We identify 6287 radio sources down to 5 sigma over 25 sq deg, and find 4758 (75.7%) have an optical counterpart. Using a variety of multiwavelength diagnostics including X-Ray luminosities, MIR colours, SED fits, optical emission lines and radio luminosity, we classify the sources into three types: low-excitation radio galaxies (LERGs), high-excitation radio galaxies (HERGs), and star-forming galaxies (SFGs). We present AGN radio luminosity functions from the ATCA XXL-S for z = 0 to 1.3 and quantify the cosmic evolution of the LERG and HERG populations. Using scaling relations to convert radio jet power to kinetic energy, we also quantify radio-mode feedback across z = 0 to 1.3.

## Mapping the Galaxy Distribution in and around Galaxy Clusters

Hwang, Ho Seong

Measurement of the mass distribution in galaxy clusters is an important test of structure formation models. Among many ways to map the matter distribution in clusters, three methods including galaxy redshift, weak lensing and X-ray surveys have been widely used. The three methods are complementary, and the combination of them is helpful for better understanding the assembly history of the cluster and understanding the systematics of each method. We present the results from extensive redshift surveys of nearby clusters focusing on the comparisons of galaxy distributions with the matter distributions from weak-lensing and/or X-ray surveys.

## František Nušl, vicepresident of the IAU 1927-1935 and inventor of the circumzenithal telescope

Hyklová, Petra

The Czech astronomer František Nušl (1867-1951) was professor of mathematics, practical astronomy and geometrical optics at Prague Charles University. His scientific contribution to astronomy consisted mainly of inventing and constructing of new astronomical and geodetical instruments. Together with his friend Josef Jan Fric, founder of the Ondrejov Observatory, he developed and improved the circumzenithal telescope (1899-1903-1906-1922-1932), a portable instrument with a mercury horizon for determining the geodetic position using the Gauss method of equal altitudes. This instrument won the gold medal at the Exposition Internationale des Arts et Techniques dans la Vie Moderne in Paris in 1937. Nusl, independently on Ernst Öpik, invented the wobbling mirror for determining the velocity of meteors by visual observation, and constructed an unique guiding system for the Ondrejov astrograph etc.            The organisational activities of Frantisek Nušl were considerably rich, too: He was one of the founders of the Czech Astronomical Society in 1917, in the years 1922-1948 he served as its president. From 1918 until his retirement in 1937 he was the director of the Ondrejov Observatory, 40 km south of capital city of Prague, lectured astronomy at the Prague university and held many popular lectures including regular courses in radio broadcasting. Frantisek Nušl was member of several commisions of  international scientific unions; he organized the 3rd General Assembly of  IUGG (International Union of Geodesy and Geophysics) in Prague 1927, and in IAU (International Astronomical Union) he was elected as Vice-President in the years 1928-1935. One can conclude that he was the main person who formed the Czech astronomy in the interwar period.

## Students as Content Creators of Creative Astronomy Outreach

Ibrahim, Alaa

Outreach enriches education and lifelong learning, fulfills the broader impact of research, and strengthens the ties between educational/research institutes and their constituents, including society, alumni, and future students. Its impact includes motivating the next generations of scientists and engineers, enhancing STEM education outside traditional classroom setting, and being a catalyst to augmenting the science and technology workforce, a key factor to a competitive society. For nearly a decade and through project-based and community-based learning, students in introductory astronomy courses in Egypt become content creators of creative astronomy outreach material that are disseminated through visits to public schools, community centers, and during stargazing events. The projects range from building hands-on demonstrations to producing educational videos that communicate essential concepts in astronomy, challenge myths and misconceptions, and enhance the overall scientific literacy of the audience. The experience offers mutual benefit to students and the audience. Besides, it inspires new forms of activities that advance the practice of outreach itself, e.g. moving from Outreach 1.0 (Taking science events to the community at public) to Outreach 2.0 where the interaction between the outreach practitioners and the local community inspires new collaborative forms of outreach.References [1] The 95 Percent Solution, John H. Falk and Lynn D. Dierking, American Scientist 98(6):486493, 2010[2] Celebrating the Culture of Science, John Durant and Alaa Ibrahim, Science, Vol. 331, Issue 6022, pp. 1242, 2011[3] Bridging the Gap between Scientists and Society in the Arab World, Alaa Ibrahim, Nature Middle East, doi:10.1038[4] Our Community-Based Learning Projects,  Vimeo.com/Science2Society

## Student and Community Engagement in Astronomy Through Experiential Learning

Ibrahim, Alaa

Fulfilling the broader impact of research is an excellent opportunity for educational activities that connect scientists and society and enhance students and community engagement in STEM fields. Here we present the experience developed in this endeavor as part of our research and educational projects that introduced educational and outreach activities that included core curriculum course development for university students from various majors, community-based learning projects, citizen science and outreach programs to school students and community members. Through these activities, students worked with the project scientists on a variety of activities that ranged from citizen science and undergraduate research to running mass experiments and community awareness campaigns through the production of short documentaries and communicating them with stakeholders and target groups, including schools and TV stations. The activities enhanced students learning and the public awareness. It also connected effectively the project scientists with college and university students a well as wider segments of the society, which resulted in a host of benefits including better scientific literacy and appreciation to the role of scientists, promoting scientists as role models, sharing the values of science, and motivating future generations to pursue a career in science.

## Is there a maximum mass for supermassive black holes?

Ichikawa, Kohei

Recent quasar surveys have revealed that supermassive black holes (SMBHs) rarely exceed a mass of MBH ~ a few * 1010 Msunduring the entire cosmic history. It has been argued that quenching of the BH growth is caused by a transition of a nuclear accretion disk into an advection-dominated accretion flow, with which strong outflows and/or jets are likely to be associated. We investigate the relationship between the maximum mass of SMBHs and the radio-loudness of quasars with a well-defined sample of ~ 105 quasars at a redshift range of 0 < z < 2, obtained from the Sloan Digital Sky Surveys DR7 catalog. We find that the number fraction of the radio-loud (RL) quasars increases above a threshold of MBH ? 2 x 109 Msun, independent of their redshifts. Moreover, the number fraction of RL quasars with lower Eddington ratios (out of all RL quasars), indicating lower accretion rates, increases above the critical BH mass. These observational trends can be natural consequences of the proposed scenario of suppressing BH growth around the apparent maximum mass of ~1010 Msun. The ongoing VLA Sky Survey in radio will allow us to estimate of the exact number fraction of RL quasars more precisely, which gives further insight into the quenching processes for BH growth.

## Optical variations of selected LMXB and HMXB systems with neutron star

Icli, Tugce

Long-term and short-term photometric variation of the selected LMXBs and HMXBs with neutron star component are studied. We obtained new VRI observations of the selected systems by using 60cm Robotic telescope and 100cm telescope at the TÜBITAK National Observatory (TUG). We combined all the available observations of the systems with our new observations. Long- and short period light variation are discussed in this study.This study is supported by the Turkish Scientific and Research Council-TÜBITAK (117F118). We thank to TUBITAK for a partial support in using T100 and T60 telescope with project number 15AT60-776, 15CT100-916 and 17BT100-1204.

## Optical variations of selected LMXB and HMXB systems with neutron star

Icli, Tugce

Long-term and short-term photometric variation of the selected LMXBs and HMXBs with neutron star component are studied. We obtained new VRI observations of the selected systems by using 60cm Robotic telescope and 100cm telescope at the TÜBITAK National Observatory (TUG). We combined all the available observations of the systems with our new observations. Long- and short period light variation are discussed in this study.This study is supported by the Turkish Scientific and Research Council-TÜBITAK (117F118). We thank to TUBITAK for a partial support in using T100 and T60 telescope with project number 15AT60-776, 15CT100-916 and 17BT100-1204.

## Low Luminosity AGNs in the Local Universe

ikiz, tuba

Galaxies are known to contain black holes (e.g.Ferrarese & Merritt 2000), whose mass correlates with the mass of their bulge. A fraction of them also has an Active Galactic Nucleus (AGN), showing excess emission thought to be due to accretion of mass by the supermassive black hole at the center of the galaxy. It is thought that AGNs play a very important role during the formation of galaxies by creating large outflows that stop star formation in the galaxy (e.g. Kormendy & Ho 2013). The aim is to detect the fraction of Low Luminosity Active Galactic Nucleus (LLAGN) in the nearby Universe. At present, they are typically found using optical spectroscopy (e.g.Kauffmann, Heckman et al. 2003), who discuss the influence of the AGN on the host galaxy and vice versa. However, optical spectra are seriously affected by extinction in these generally very dusty objects, and therefore can only give us partial information about the AGN. I used a newly-found method, and apply it to the S4G(The Spitzer Survey of Stellar Structure in Galaxies) sample, a large, complete, sample of nearby galaxies, which I am studying in detail with a large collaboration, to detect the fraction of low luminosity AGNs, and to better understand the relation between AGNs and their host galaxy which is thought to be crucial for their formation. I will present the results of our study based on AGN fractions in nearby universe.

## Titan’s polarization phase curves with Cassini/ISS

Ilic, Nikoleta

The sunlight reflected by Titan’s atmosphere is strongly polarized at phase angles near quadrature. This Rayleigh-like behavior has been a key clue for the understanding of the aggregate nature of Titan’s ubiquitous atmospheric haze. We are preparing Titan’s polarization phase curves with data collected with Cassini’s Imaging Science Subsystem. The Cassini/ISS dataset covers the spectrum from the UV to the NIR, and phase angles from nearly zero degrees (full illumination) to 150 degrees, thereby extending the observations made by the Voyager and Pioneer spacecraft decades ago. The Cassini/ISS dataset confirms the older trends in Titan’s polarization, but also shows new insight thanks to the relatively good phase sampling and to the availability of data at wavelengths affected by methane absorption. Since we now have spectrally-resolved phase curves in both brightness and polarization, we are investigating the optimal way to combine that information towards the optimal characterization of Titan’s atmosphere. The question is also relevant to the prospective characterization of exoplanets.

## Binary nature of fast rotating Be star Pleione and the reflection to it's circumstellar disk evolution

Iliev, Lubomir

Pleione is a classical Be star well known with it’s cyclic transitions between Be-, shell- and normal B spectral phases.It’s nature as a binary system was discussed by McAlister et al. (1989), Gies et al. (1990), Luthardt & Menchenkova (1994) and Nemravova et al. (2010). We present results of the tracing the evolution of the dimensions of emitting regions of the circumstellar disk of Pleione connected with the binary nature of the star.

## Early light curve of SN 1604 and constraints on its progenitor star system

Im, Myungshin

Type Ia supernova (SN Ia) is believed to occur due to the explosion of a white dwarf (WD) in a binary system. Yet, it is unclear if the companion star of the exploding WD is another WD or a non-degenerate star such as a main sequence or red giant star. Recently, the early light curve, the light curve one to two days within the explosion of SNe, is recognized as a powerful tool to estimate the size of the companion star. We apply this method on SN 1604, SN Ia,  where an extensive daily light curve is available from Korean and European historical records. Our analysis shows that SN 1604 is a rather abnormal, faint SN Ia, and the early light curve is best explained with the presence of a companion star with the size of about 1 to 10 solar radius. This result suggests that SNe Ia with abnormal properties may originate from single degenerate binary systems.

## Significant roles of accretion rings in X-ray binaries

Inoue, Hajime

X-ray light curves of three X-ray pulsars, Her X-1, LMC X-4 and SMC X-1, folded with their respective super-orbital periods, are shown to be well reproduced by a model that X-rays from a compact object towards us are periodically obscured by a precessing ring at the outermost part of an accretion disk around the central object. A situation is considered that matter from a companion star flows into a gravitational field of a compact star and initially forms a circular ring around the compact star under a balance between the centrifugal force and the gravitational force.  A simple energetics-argument indicates that a precession of such a ring is possible to be excited.  From the best fir parameters of the model fit to the super-orbital light curves, we see that the optical depth of the accretion ring is commonly around unity for Compton scattering and that the ring should suffer from a significant effect of X-ray heating from the central X-ray source.  By considering why and how such an accretion ring is realized, the following evolution of the ring matter is suggested:  Matter from the companion star initially forms a geometrically thick ring and accumulates there until the optical depth becomes around unity.  Then, the matter in the thick ring gradually cools down under a balance between X-ray heating and radiative cooling, and shrinks to a geometrically thin ring at the cross section center of the ring.  Angular momenta of the rotating matter are effectively transferred from the inside to the outside in the thin ring and the inside matter finally falls through a geometrically thin accretion disk towards the central compact object.  This scenario on the outermost part of accretion disks can well explain several observational aspects of accreting X-ray binaries.

## Spatially resolved emission line observations of galaxies at the reionization epoch

Inoue, Akio

One of the major science goals of extremely large telescopes (ELTs) is to explore the galaxy formation at the highest redshift. Emission lines from gasous nebulae in galaxies have a plenty of information about the physical and chemical conditions which are key ingredients to complete the galaxy formation theory. Especially, such information in a spatially resolved way is the Holy Grail. Therefore, every ELT will have its own integral-field spectroscopic instrument. Recently, we have successfully resolved the spatial distribution of far-infrared fine structure lines of [OIII] 88 micrion and [CII] 158 micron in a galaxy at z=7.15 with ALMA. Here, we present an emission line ratio map as a showcase for the future ELTs' integral-field spectroscopy targeting the rest-frame ultraviolet and optical emission lines in high-z galaxies.

## Expansive Public Outreach in Thailand - Far and Wide

Insiri, Wichan

In Thailand, the network of astronomy has been a success as it has seen an expansive impact to the Thai society as a whole since the establishment of the National Astronomical Research Institute of Thailand (NARIT). We simply put the public as our priority. Innovation-driven economy is Thailand’s national agenda and astronomy has been one of the forces behind the success en route to the knowledge-based society. We have seen sharp increase in the awareness of science and technology as can be seen through the escalation of activities in relation to astronomy or even other fields of science and technology. This has also been felt through the surge of government’s spendings on research and development in science, technology and innovation in the past years. All combined, the climate of astronomy and its related fields together with public outreach and astronomy popularization have utilised all the resources in good use

## An Origin of Accelerating Star Formation

Inutsuka, Shu-ichiro

Recent theoretical work on phase transition dynamics of ISM has shown that the formation of molecular clouds requires multiple episodes of supersonic compression. This finding enables us to create a scenario of molecular cloud formation as the interacting shells or bubbles in galactic scale. This picture naturally explains the accelerated star formation over many million years that was previously reported by stellar age determination in nearby star forming regions.

## ‘Intriguing’ scaling relations of dwarf irregular galaxies

Iorio, Giuliano

Scaling relations of galaxies represent an important benchmark for cosmological simulations and for theories of galaxy formation and evolutions.  The properties of scaling relations for dwarf galaxies are still not well known due to the large uncertain on the estimate of dwarf properties. In this context, the kinematics of HI discs of dwarf irregular galaxies (dIrrs) represents a fundamental piece of information to explore certain scaling relations. Using robust estimates of the HI disc kinematics for a sample of 17 dIrrs, we present an analysis of three ‘intriguing’ scaling relations. We analysed the Baryonic Tully-Fisher relation and the Radial Acceleration Relation at the very low mass scales traced by dIrrs. We found that the relations found for the galaxies in our sample are compatible with what is found for more massive galaxies in contraposition with what is predicted by cosmological simulations.  Finally, we found a clear correlation between the kinetic energy held in the HI turbulent  motions  and the star formation rate density of the dIrrs. Comparing this relation with the supernova explosions theories,  we found that the turbulence in the HI discs can be sustained by the star formation activity assuming an average efficiency of about 30% in transferring the supernova explosions energy into the ISM.The results of this work represent relevant tests for galaxy formation theories and for cosmological simulations, moreover, they reveal the fundamental role of the star formation feedback in feeding the turbulence in the ISM.

## Tidal fields and mass estimate of dSphs: the case of Sculptor

Iorio, Giuliano

The study of the dynamics of dwarf galaxies is one of the essential keys to understand their formation and their evolution. The dwarf spheroidal satellites of the Milky Way are close enough to be explored in details. In particular,  it is possible to estimate the total matter content using the kinematics of the stars.  The interpretation and the modelling of these data rely on equilibrium models in which we assume that the stellar kinematics is a genuine tracer of the galactic potential.  However, these objects are orbiting in the tidal field of the Milky Way and it could be possible that the velocity dispersion is inflated by stripped stars along the line of sight. Therefore, the estimate of the dark matter content of these objects could be biased. In this talk, I will present detailed N-body simulations focused on the reproduction of the properties of the Sculptor dwarf spheroidal. Using the most recent and robust measurements of the proper motion of Sculptor and conservative assumptions on the Milky Way mass, we tuned the initial properties of the N-body realisation to reproduce the observed properties we see today.  Finally, we analysed the final snapshot of the simulations as is done for real data.We found that, even in the worst case (closest epicentral passages), the kinematics of the stars in Sculptor is not affected by the tidal field of the Milky Way. Therefore, we conclude that the method commonly used to retrieve the mass in dwarf spheroidals are capable to return robust estimates of the total matter content of Sculptor.

## The solar Lense-Thirring effect and BepiColombo

Iorio, Lorenzo

We analytically calculate the time series for the perturbations induced by a general disturbing acceleration on the mutual range and range-rate of two test particles A, B orbiting the same spinning body of mass M, angular momentum S, equatorial radius R and oblateness J2. We apply it to the general relativistic Lense-Thirring effect, due to the primary's spin S , and the classical perturbation arising from its quadrupole mass moment J2 for arbitrary orbital geometries and orientation of the source's symmetry axis. The Earth-Mercury range and range-rate are nominally affected by the Sun's gravitomagnetic field to the 10 m, 10-3 cm s-1 level, respectively, during the extended phase (2026-2028) of the forthcoming BepiColombo mission to Mercury whose expected tracking accuracy is of the order of about 0.1 m, 2 x 10-4 cm s-1. The competing signatures due to the solar quadrupole J2, if modelled at the 10-9 level of the latest planetary ephemerides INPOP17a, are nearly 10 times smaller than the relativistic gravitomagnetic effects.

## Near-Earth object population and formation of lunar craters during the last billion of years

Ipatov, Sergei

We analyzed diameters of lunar craters in the region of the Oceanus Procellarum with age TOS<1.1 Gyr. The ratio rOS of the area of the considered region to the full surface of the Moon is 0.176. Based on the formula (16) from [1] we concluded that the diameter D of the crater that is produced by an impactor with a diameter di=1 km is 19.1 km and 18.4 km for the impact velocity equal to 19.3 km/s and 18 km/s, respectively. The number Nobs of craters with D greater than 18 or 19 km in the considered region is 49. The number N1 of near-Earth objects (NEOs) with diameter d>1 km is considered to be about 920. The characteristic time TE elapsed before a collision of a NEO with the Earth is estimated to be about 100 Myr (up to 120 Myr). The ratio pEM of probabilities of collisions of NEOs with the Earth to that with the Moon is about 20. Based on the above values we estimated the number of impacts of NEOs with d>1 km onto the considered lunar region as Nest=N1·rOS·TOS/(TE·pEM)˜920·0.176·1.1/(0.1·20)˜89. The ratio Nest/Nobs is 1.8. For greater values of TE and pEM, the ratio can be a little smaller, but probably it is still greater than 1.5. The above estimates show that the number Nobs of observed craters is less than the estimated number Nest, i.e. the mean value of TE·pEM calculated for the last billion of years could be greater than its present value, or N1 or TOS should be smaller for calculation of Nest. A recent catastrophic disruption of a large main-belt asteroid [2] could increase N1 compared to its mean value for a whole 1 Gyr interval. The difference in the values of Nest and Nobs can be also caused by that craters with a greater age less survive. Results of our analysis of the number of craters of different sizes are in accordance with the earlier conclusion that the number of impactors with a diameter d>Dp is proportional to Dp-2/3. [1] Werner S.C., Ivanov B.A. Treatise on Geophysics (Second Edition),2015,10,327–365. [2] Bottke W. et al. Nature, 2007,449,48-53

## Formation of trans-Neptunian satellite systems at the stage of rarefied condensations

Ipatov, Sergei

The angular momenta used by Nesvorny et al. [1] as initial data in their calculations of contraction of condensations leading to formation of trans-Neptunian binaries could be acquired at collisions of two condensations that were moving before collisions in circular heliocentric orbits [2]. Initial angular momenta of condensations were not enough for formation of binaries. The parental condensation with radius close to its Hill radius that grew by accumulation of small objects could get the angular momentum at which a satellite system of a trans-Neptunian object could form. However, in this case the angular momentum of all satellite systems (e.g., binaries) would be positive. Actually about 40% of discovered trans-Neptunian binaries have negative angular momentum. Depending on heliocentric orbits of two colliding condensations, the angular momentum at their collision can be positive or negative. For the model of formation of binaries at the stage of rarefied condensations, I explained [3] the formation of prograde and retrograde rotation of discovered trans-Neptunian binaries, the inclinations of orbits of secondaries at different ratios of diameters of the secondary to the primary, the inclinations of orbits of secondaries at different orbital elements of heliocentric orbits of binaries, the separation distances at different heliocentric orbits, the orbits of binaries at different separation distances. The work was supported  by the RFBR grant ? 17-02-00507 (angular momenta of condensations needed for formation of binaries) and by the Program of the Fundamental Studies of the Presidium of RAS N 28 as a part of Russian state program for GEOKHI N 00137-2018-0033 (origin of orbits of secondaries in binaries). [1] Nesvorny D. et al. Astron. J. 2010. 140. 785-793. [2] Ipatov S.I. Solar System Research. 2017. 51. 321-343. https://arxiv.org/abs/1801.05217. [3] Ipatov S.I. Solar System Research. 2017. 51. 409–416. https://arxiv.org/abs/1801.05254

## Observing with CHEOPS: the CHEOPS Guest Observers Programme

Isaak, Kate

CHEOPS (CHaracterising ExOPlanet Satellite) is the first exoplanet mission dedicated to the search for transits of exoplanets by means of ultrahigh precision photometry of bright stars already known to host planets. It is the first S-class mission in ESA’s Cosmic Vision 2015- 2025. The mission is a partnership between Switzerland and ESA’s science programme, with important contributions from 10 other member states.Foreseen to be ready to launch at the very end of this year, CHEOPS will provide the unique capability of determining radii of planets in the super-Earth to Neptune mass range to 10% precision. It will also provide accurate radii for new planets discovered by the next generation of ground-based or space transit surveys (from super-Earth to Neptune-size). The high photometric precision of CHEOPS will be achieved using a photometer covering the 0.33 - 1.1um waveband, designed around a single frame-transfer CCD which is mounted in the focal plane of a 30 cm equivalent aperture diameter, f/5 on-axis Ritchey-Chretien telescope.20% of the observing time in the 3.5 year nominal mission will be available to the Community through the Guest Observers Programme that will be run by ESA. for the first year of observing will come out in Summer 2018.In this contribution  I will give an overview of observing with CHEOPS, with a particular focus on the ESA-run CHEOPS Guest Observers Programme.

## Dual-channel AGN feedback: the radiative-mode

Ishibashi, Wako

Two main modes of AGN feedback are known in nature: the radiative-mode and the jet-mode, which operate in different accretion states at different cosmic epochs. While jet-mode feedback has strong observational evidence, the radiative-mode is much more difficult to directly observe, due to obscuration. Yet, major progress has been made over the last few years, with powerful outflows on galactic scales being detected in radio-quiet AGNs. However, the physical mechanism actually driving the galactic outflows remains to be elucidated. We consider AGN feedback driven by radiation pressure on dust. We show that AGN radiative feedback can account for the observed outflow dynamics and energetics, provided that radiation trapping is properly taken into account. Such radiative feedback is capable of efficiently removing the obscuring dusty gas, and may thus provide a natural physical interpretation for the observed starburst-AGN co-evolutionary sequence. Furthermore, the propagation of radiation pressure-driven dusty outflows may even contribute to the metal enrichment of the circum-galactic medium. I will discuss how radiative-mode feedback may be equally important than jet-mode feedback in shaping the evolution of the host galaxy and surrounding environment.

## Early Emission through Free Neutron Ejection in Binary Neutron Star Merger

Ishii, Ayako

Gravitational waves (GWs) from a binary neutron star merger (NSM) were observed by advanced LIGO and Virgo on August 2017 for the first time. Soon after the detection, electromagnetic follow-up observations were performed, and the electromagnetic counterpart was detected over the wide wavelength range. The first electromagnetic emission was detected at 10.9 h after the merger event. If the earlier emission from the NSM had been detected, it would have provided us with rich information about the NSM. For example, the ejected material from NSM may include free neutrons in the outermost layer. The layer might contribute the early emission through beta decay in a time scale of hours (Metzger et al. 2015). But the emission powered by decays of free neutrons is not fully understood because the existence of the free neutron layer was explored by smoothed particle hydrodynamics simulation with a small number of particles.   We numerically investigate the possibility for the existence of the free neutron layer and the early emission through decays of free neutrons. We systematically study a wide parameter space of the size of the merging neutron stars and the energy involved in the shock waves. As a result, it is found that the mass of remaining free neutron is 10^{-7} to 10^{-6} Msun, which is smaller than the previously expected by more than two orders of magnitudes. This is due to the p(n, ?)d reaction, which was not taken into account in previous studies. We estimate that the total electromagnetic luminosity is about 4×10^{41} erg s^{-1} at ~30 min after the merger and that the emission has a peak in the ultraviolet wavelengths.

## Growth of massive black holes in dusty clouds: impacts of relative velocity between dust and gas

Ishiki, Shohei

Recent observations have suggested the existence of a large amount of dust around supermassive black holes (SMBHs) in the early universe (e.g. Maiolino et al. 2004). In dusty clouds, the growth of black holes can be significantly regulated due to strong radiation force on dust grains. Yajima et al. (2017) recently showed that the accretion on to intermediate-mass black holes (IMBHs) in dusty clouds are significantly suppressed compared with dustless clouds because of the strong radiation force on dust grains. They, however, assumed that the dust and gas are completely coupled. This assumption might be invalid in the vicinity of black holes. The relative velocity between dust and gas is likely to have impacts on the accretion rate._x005F We here investigate the impacts of the relative motions of dust and gas on the accretion rate onto IMBHs with the mass of 105 Msun by using one-dimensional radiation hydrodynamic simulations in clouds with initial gas densities of nH = 10 and 100 cm-3. To investigate the effect of grain size on the gas accretion, we introduce two additional fluid components which describe large (0.1 μm) and small (0.01 μm) dust grains in the simulations as we did in Ishiki et al. (2018)._x005F We show that the accretion rate is reduced due to the radiation force. We show that the dust-to-gas mass ratio significantly changes in HII regions because of the relative motions of dust and gas. The decoupling of dust from gas alleviates the suppression of black hole growth compared with the complete coupling case. This effect may allow moderate growth of black holes even in dusty clouds.

## How to ensure different organisations in different countries join forces to communicate one project

Isidro, Mathieu

The Square Kilometre Array (SKA) project is an international effort involving 20 countries on 5 continents to build the world’s largest radio telescope. One of its many challenges is coordinating a global communications effort to maximum effect and impact, both for the project as a whole and for its individual partners. With those partners in different timezones & continents with different interests, how do you ensure a joined-up approach across all project communications?Building on the theme of Finding Common Purpose and Implementing Coordinated Action, we will explore how we manage a global science & engineering partnership with communications colleagues spread over 20 timezones to best leverage local communications opportunities and support one another's strategic objectives while ensuring a strong brand and unified message for the project. Focusing on lessons learnt, we will discuss ways of working and workflows and highlight successes and challenges of some of the communication campaigns we have undertaken in the past five years.

## Sunspot group tilt angles for cycles 19-24

Isik, Seda

The tilt angle of sunspot groups is an important quantity, as it determines the amount of signed flux transported to the solar poles. To date, however, there has been only a few observational studies on cycle-averaged tilt angles. Using the digitised archive of sunspot drawings produced at Kandilli Observatory, we measured group tilt angles for the period 1958-2017, and compared our results with the Mount Wilson (MWO), Kodaikanal (KSO) and Debrecen Photoheliographic (DPD) databases. The average shape of Joy's law as well as cycle-averaged tilt angles show similar trends with DPD. We found a much weaker anti-correlation of the mean tilt angle (normalised to latitude) with cycle strength than was reported using MWO and KSO data.

## Emergence and surface transport of magnetic flux in Sun-like stars

Isik, Emre

Forward modelling of surface magnetism can be highly useful when interpreting photometric time series of Sun-like stars, as well as when reconstructing solar irradiance. We set up a theoretical framework based on the solar butterfly diagram, to study processes of flux emergence and transport on Sun-like stars. We take a semi-synthetic solar butterfly diagram of sunspot group emergence and map the emergence latitudes back to the base of the convection zone, using numerical simulations of rising flux tubes under the effects of stratification, drag force, and internal differential rotation. Transforming the base distribution to the surface for a given rotation rate, we determine the emergence latitudes and tilt angles of flux loops for the input rotation rate and activity level. Running a surface flux transport (SFT) model, we simulate the diffusive-advective evolution of the radial field at the surface. As the rotation rate increases, an inactive gap opens around the equator, reaching a half-width of 20º for 4 and 8 times the solar rotation rate. Between these two rotation rates, we find that polar spots start to form by accumulation of follower polarity flux. For 4 and 8 times the solar rotation rate, the cycle-averaged spot coverage becomes 2% and 10%, respectively, compared to the solar value of 0.2%, compatible with stellar observations.

## Orbital resolved spectroscopy of GX 301-2: wind diagnostics

Islam, Nazma

GX 301-2, a bright high-mass X-ray binary with an orbital period of 41.5 days, exhibits stable periodic orbital intensity modulations with a strong pre-periastron X-ray flare. Several models have been proposed to explain the accretion at different orbital phases, invoking accretion via stellar wind, equatorial disc, and accretion stream from the companion star. From the orbital resolved spectroscopic study of GX 301–2 with the X-ray all sky monitor MAXI, we found a very large equivalent width of the iron line for a small value of the column density in the orbital phase range 0.10–0.30 after the periastron passage. The orbital dependence of the spectral parameters favours accretion on to the neutron star occurring via a high density accretion stream plus stellar wind of the companion. We further investigate the characteristics of the accretion stream with an ASTROSAT LAXPC and SXT observation of the system.

## A curious case of HMXB 4U 1700-37

Islam, Nazma

4U 1700-37 is an eclipsing High Mass X-ray binary in a short orbital period of 3.412 days. In the absence of detectable pulsations, the orbital evolution is determined from the eclipse timing measurements, both from archival measurements as well as new measurements from long-term light curves obtained with the all sky monitors RXTE-ASM, Swift-BAT and MAXI-GSC. The orbital period decay rate of the system is estimated to be 10^{-7} /yr, smaller compared to its previous estimates. The mid-eclipse times and the eclipse duration measurements obtained from 10 years long X-ray light curve with Swift-BAT are used to separately put constraints on the eccentricity of the binary system and measure any apsidal motion. We carry out a deepest search for pulsations and Cyclotron Resonance Scattering Feature (CRSF) using a 40 kilosec ASTROSAT LAXPC observation. These results will provide some newer insights into the nature of the compact object, which is either a very high mass neutron star or a very low mass black hole.

## SURFACE PHOTOMETRY OF PROPLYDS IN THE ORION NEBULA

Ismayilov, Nariman

The Orion Nebula (M42, NGC1976) is the unique space laboratory for studying of physical processes at the initial stage of starformation. Proplyds are small star-shaped objects that have comet-like forms which are consisting of the bright head and tail. In this report we present the results of studies of the structure of 11 proplyds located near the star θ1 OriC by using the surface photometry method. The observational material was taken from the archive MAST HST (https://archive.stsci.edu/hst/). CCD images were obtained with a resolution of 0.05" and in different filters. For research we have used the software MIDAS._x005F We studied the surface brightness distribution of proplyds along the axes, one of which passes through the head and tail (the Y axis), and the second through the brightest center and perpendicular to the first direction (the X axis). In all case, the spatial orientation of each axis was taken into account and their absolute sizes were determined. It is shown that the brightness along these axes shows non-linear bell-shaped distribution which can be descripted by 3 degree polynomial. For different proplyds, the maximum linear dimensions are reached from 60 to 200 AU along different axes. On average, the ratio of the linear sizes along these axes directions is obtained as Dy: Dx = 2: 1, i.e. the ratio of dimensions along the tail is twice large than in width._x005F A noticeable difference in the sizes of the prodlyds from the images obtained in different wavelength was found. For example, the linear sizes of proplyds in the blue band (λ 3870 Å) have a more asymmetric appearance and, on average, linear sizes, about 20-50% greater than the sizes in red band (λ 7727 Å). This indicates that the gas component matter around the proplyds is much larger than of the dust component.

## Master light curve analysis of the Classic T Tauri type star DN Tau

Ismayilov, Nariman

The results of analysis of the summary light curve of the classical T Tauri star (CTTS) DN Tau, obtained from observations for over 50 years, are presented. It is shown that the amplitude of seasonal variations in brightness is ~ 0.5 mag. The average for year light curve shows long-time slow variations with a characteristic time of about 25 years._x005F The distribution of the brightness variations in the V and R bands is carried out a symmetric form, while asymmetry is observed in the U and B bands, which is occurred for often flare type increases in the brightness. The dependence of V brightness with color indexes B-V, U-B and V-R is well described in the simple cool spot model, where the temperature of the spot is lower by 800 K than the mean photosphere temperature of the star._x005F The dependence of the brightness V on the color indices B-V and V-R is well described in the cold spot model, at a spot temperature below 800 K from the temperature of the photosphere of the star. For different observation seasons, a difference in the value of the previously detected photometric period of 6.3 days was found within a few tenths of a day. For the average value of this period for different seasons 6.231 ± 0.089 days were obtained. The displacement the phases of minimum of this period were found from data of different observations seasons. In addition, two characteristic values ​​of the steepness in the light curve are observed. In the first case, the brightness variation has a high speed, in the second case a relatively low rate of brightness changes with time. It is shown that the displacement of the phase of the period can arise because of migration of spots.

## Proto-BCG candidates at z~4 by using HSC-SSP data

Ito, Kei

Brightest Cluster Galaxy (BCG) is the brightest and the most massive galaxy in a galaxy cluster. In nearby universe, BCGs are known to have distinguished characteristics compared to other cluster galaxies and field galaxies. Theoretical research predicts that most of the stellar mass was already formed at z~3 (De Lucia and Blaizot 2007); therefore, it is a key to find the progenitor of BCGs (proto-BCGs) at high-redshift in order to understand the formation of BCGs. However, it has been difficult to systematically study the high-z BCGs due to a small size of previous protocluster sample. Here, we report our survey of proto-BCGs candidates at z~4 by using Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). We are ongoing the largest survey of high-redshift protoclusters to date by using imaging data produced by HSC-SSP. We constructed g-dropout galaxies catalog and found 179 protocluster candidates at z~4 (Toshikawa et al. 2018) over 121 square degrees. This is roughly ten times larger than any previous survey, enabling us, for the first time, to also construct a large sample of proto-BCGs. After removing contaminants (e.g. foreground galaxies or stars) which dominate bright-end, we identified 58 proto-BCGs candidates by 1) selecting the brightest member galaxy in each protocluster and 2) requiring the magnitude difference between the fifth and the first in a region is greater than 1.1 mag in i-band. Interestingly, members of protoclusters with proto-BCGs are found to be redder in (i-z), indicating that the dust extinction is more severe than that in field galaxies and members of protoclusters without proto-BCGs. This suggests that proto-BCGs may trace more developed structures than those without proto-BCGs. Also, we report the result of the morphological analysis in this poster.

## VLT / KMOS view of the explosive outflow in Orion BL/KL

Itrich, Dominika

Orion BL/KL hosts a unique outflow containing more than 100 individual jets resembling those of young stellar objects. The directions of the jets strongly suggest an explosive origin linked to the decay of a non-hierarchical system of massive stars (Youngblood et al. 2016). Here, we present near-IR (1.4-2.4 µm) spectral maps of these "Orion fingers" using the K-band Multi Object Spectrograph (KMOS) at VLT. The H2 and [FeII] lines are used to determine gas physical conditions and dynamics. The observations reveal the properties of the shocks in this unique region at unprecedented detail.

## Semi-analytical theory of the axially symmetrical Moon's rotation

iVANOVA, TAMARA

In the present paper the trigonometric theory of the rigid-body axially symmetrical Moon's rotation is constructed in the framework of the general planetary theory avoiding the non-physical secular terms and involving the separation of the long-period and short-period angular variables, both for planetary-lunar motions and Moon's rotation. The combined system of the equations of motion for the principal planets and the Moon and the equations of the Moon's rotation is reduced to the autonomous secular system describing the evolution of the planetary and lunar orbits independent of the Moon's rotation and the evolution of the Moon's rotation depending on the orbital planetary and lunar evolution. The secular system is solved in the trigonometric form. As a result, the theory of the axially symmetrical Moon's rotation is presented by means of the power series in evolutionary variables withquasi-periodic coefficients in mean longitudes of the planets and the Moon. All analytical calculations were performed by means of the Poisson series processor.

## GC58 Constraints on the dark matter core inside the neutron stars

Ivanytskyi, Oleksii

We study a compatibility of the dark matter condensation inside the neutron stars with the observational constraints on the properties of these astrophysical objects. Effects of the baryon-lepton matter are taken under control based on the well tested novel equation of state of nuclear matter, which is able to fulfill a rich collection of constraints from nuclear physics and heavy ion collision experiments. Considering the dark matter as a free Fermi gas coupled to usual matter only by gravity we explicitly introduce mass and quantum mechanical degeneracy of these particles to the problem. Integration of the Tolman-Oppenheimer-Volkoff equation allows us to obtain the mass-radius diagram of neutron stars for different concentrations of dark matter particles and their masses from 100 MeV to 1 TeV. We argue, that concentrations of the dark matter typical for the Milky Way galaxy do not allow its particles to be heavier than about 100 GeV. This result can serve as a constraint for beyond the Standard Model theories aiming to explain the dark matter nature in terms of WIMPs.

## Dusty plasma effects in the atmosphere of Mars and near the Martian Surface

Izvekova, Yulia

Dusty plasma effects in the Martian atmosphere are discussed. A specific feature of the Martian atmosphere is the presence of dust grains in a wide range of altitudes. Taking into account the presence of the Martian ionosphere and the high conductivity of the medium at lower altitudes, the appearance of plasma systems in the Martian atmosphere can be considered quite a common phenomenon. Special attention is paid to Dust Devils that frequently form in the Martian atmosphere and can efficiently lift dust grains. The processes of dust grain charging as a result of triboelectric effect and generation of electric fields in a Dust Devil are discussed. The dynamics of dust grains in such a vortex is simulated with allowance for their charging and the generated electric field._x005F This work was supported by the Russian Foundation for Basic Research (project no. 18-02-00341).

## Can the brightest stellar explosions be triggered by gas inflows ?

Izzo, Luca

The advent of integral-field unit spectrographs allowed us to analyse with great details the galaxies and the direct environment where the brightest stellar explosions, like GRBs and SLSNe, formed and evolved. Long-time observations have revealed that GRBs and SLSNe form in the lowest-metallicity regions of their hosts. At same time, the inflow of pristine gas can enrich the galaxy environment of low-metallicity gas and also trigger burst of star-formation rate. Presence of this pristine gas can also be inferred from HI radio observations, as well as in the distribution of the brightest star-forming regions in host galaxies. We present some evidences for the possible presence of gas inflow interactions in some host galaxies, concentrating on the specific cases of GRB 100316D and SLSN 2017egm.

## OGLE-ing the Magellanic System: Three-Dimensional Structure

Jacyszyn-Dobrzeniecka, Anna

I will present a three-dimensional structure of the Magellanic System using over 9000 Classical Cepheids (CCs) and almost 23000 RR Lyrae (RRL) stars from the OGLE Collection of Variable Stars. Given the vast coverage of the OGLE-IV data and very high completeness of the sample we were able to study the Magellanic System in great details.Lately, we have very carefully studied once again the distribution of both types of pulsators in the Magellanic Bridge area. We showed that there is no evidence of an actual physical connection between the Clouds in RRL stars distribution. We only see the two halos overlapping. There are few CCs in the Magellanic Bridge area that seem to form a genuine connection between the Clouds. Their on-sky locations are very well correlated with young stars and neutral hydrogen distribution.CCs in the LMC are situated mainly in the bar that shows no offset from the galaxy plane. The norther arm is also very prominent. Moreover, it is located closer to us than the entire sample. The CCs in the SMC have a non-planar distribution that can be described as an ellipsoid extended almost along the line of sight. RRL stars revealed a very regular distribution in both Magellanic Clouds. We fitted triaxial ellipsoids to our LMC and SMC RRL samples.

## OGLE-ing the Magellanic System: Three-Dimensional Structure

Jacyszyn-Dobrzeniecka, Anna

I will present a three-dimensional structure of the Magellanic System using over 9000 Classical Cepheids (CCs) and almost 23000 RR Lyrae (RRL) stars from the OGLE Collection of Variable Stars. Given the vast coverage of the OGLE-IV data and very high completeness of the sample we were able to study the Magellanic System in great details.Lately, we have very carefully studied once again the distribution of both types of pulsators in the Magellanic Bridge area. We showed that there is no evidence of an actual physical connection between the Clouds in RRL stars distribution. We only see the two halos overlapping. There are few CCs in the Magellanic Bridge area that seem to form a genuine connection between the Clouds. Their on-sky locations are very well correlated with young stars and neutral hydrogen distribution.CCs in the LMC are situated mainly in the bar that shows no offset from the galaxy plane. The norther arm is also very prominent. Moreover, it is located closer to us than the entire sample. The CCs in the SMC have a non-planar distribution that can be described as an ellipsoid extended almost along the line of sight. RRL stars revealed a very regular distribution in both Magellanic Clouds. We fitted triaxial ellipsoids to our LMC and SMC RRL samples.

## Magnetic fields along the pre-main sequence: new magnetic field measurements of Herbig Ae stars using high resolution HARPS spectropolarimetry

Jaervinen, Silva

Herbig Ae/Be-type stars are analogs of T Tauri stars at higher masses. Since the confirmation of magnetospheric accretion using Balmer and sodium line profiles in the Herbig Ae star UX Ori, a number of magnetic studies have been attempted, indicating that about 20 Herbig Ae/Be stars likely have globally organized magnetic fields. The low detection rate of magnetic fields in Herbig Ae stars can be explained by the weakness of these fields and rather large measurement uncertainties. The obtained density distribution of the root mean square longitudinal magnetic field values revealed that only a few stars have magnetic fields stronger than 200G, and half of the sample possesses magnetic fields of about 100G or less. These results call into question our current understanding of the magnetospheric accretion process in intermediate-mass pre-main sequence stars, as they indicate that the magnetic fields of Herbig Ae/Be stars are by far weaker than those measured in their lower mass classical T Tauri star counterparts, usually possessing kG magnetic fields. We report on the results of our analysis of a sample of presumably single Herbig Ae/Be stars based on recent observations obtained with HARPSpol attached to ESO's 3.6m telescope. Knowledge of the magnetic field structure combined with the determination of the chemical composition are indispensable to constrain theories on star formation and magnetospheric accretion in intermediate-mass stars. As of today, magnetic phase curves have been obtained only for two Herbig Ae/Be stars, HD101412 and V380 Ori.

## Studying the accretion geometry of X-ray pulsar GX 1+4 in a peculiar state

Jaisawal, Gaurava K

We present detailed spectral and timing studies using a NuSTAR observation in 2015 October of GX 1+4 during an intermediate intensity state. The measured spin period of 176.778 s is found to be one of the highest value since its discovery. In contrast to a broad sinusoidal-like pulse profile, a peculiar sharp peak was observed in profiles below 25 keV. The profiles at higher energies were found to be significantly phase-shifted to the soft X-ray profiles. Broadband energy spectra of GX 1+4, obtained from NuSTAR and Swift observations, were described with various continuum models. Among these, a two component model consisting of a bremsstrahlung and a blackbody component was found to best-fit the phase-averaged and phase-resolved spectra of the pulsar. Physical models were also used to investigate the emission mechanism in the pulsar. Based on the results obtained from fitting physical models to the data, the magnetic field strength of GX 1+4 was estimated to be in ~(5--10)x10^12 G range. Phase-resolved spectroscopy of NuSTAR observation showed a strong blackbody emission component in a narrow pulse phase range. This component was interpreted as the origin of the peculiar peak in the pulse profiles below 25 keV. The size of emitting region was calculated to be ~400 m. The bremsstrahlung component was found to dominate in hard X-rays and explains the nature of simple profiles at high energies.

## Magnetic and kinematic characteristics of very fast CMEs in 24th solar cycle

Jang, Soojeong

It is important to understand very fast CMEs which are the main cause of geomagnetic storms and solar particle events (SPEs). During this solar cycle 24, there are 10 very fast CMEs whose speeds are over 2000 km/s. Among these, there were only two front-side events (2012 January 23 and 2012 March 7) and they are associated with two major flares (M8.7 and X5.4) and the strongest SPEs (6310 pfu and 6530 pfu). They have similar characteristics: there were successive CMEs within 2 hours in the same active region. We analyze their magnetic properties using SDO HMI magnetograms and kinematic ones from STEREO EUVI/COR1/COR2 observations. We can measure their speeds and initial accelerations without projection effects because their source locations are almost the limb. Additionally, we are investigating magnetic and kinematic characteristics of 8 backside events using AI-generated magnetograms constructed by deep learning methods.

## Rotating stellar populations and morphology analysis in dSph galaxies, possible hints to understand their formation and evolution.

Jara, Alex

According to the Lambda-CDM cosmological model, dwarf spheroidal (dSph) galaxies are the basic building blocks for the formation of bigger structures, because of their high velocity dispersions and low luminosities, they are thought to be the most dark matter (DM) dominated objects in the universe. There are several models that attempt to explain their formation and evolution invoking two body interactions, e.g., resonant stripping or tidal stirring, but they have difficulty explaining the formation of isolated dSph galaxies. Another formation scenario is the dissolving star cluster model (Assmann et al. 2013, Alarcon et al. 2017), according to this model dSph galaxies were formed by the fusion and dissolution of several star clusters (SCs) formed in a giant molecular gas cloud within a DM halo. Simmulations predict kinematic substructures formed by stars following similar orbits and clumps of stars formed for star cluster which were not entirely dissolved. In this work we will compare simulations of the dissolving star cluster model with observational data.

## Heating mechanisms in accretion disks around young stellar objects

Jatenco-Pereira, Vera

Accretion disks are observed around young stellar objects such as T Tauri stars. In order to complete the star formation, particles in the disk need to loose angular momentum in order to be accreted into the central object. The magneto-rotational instability (MRI) is probably the mechanism responsible for a magneto-hydrodynamic (MHD) turbulence that leads to disk accretion, which implies the disk particles to be coupled with the magnetic filed lines. As the temperatures of the particles in the disk are low, the ionization rates are also very small. In order to increase the disk temperature, besides the viscous heating mechanism often included in the models by means of the alpha-prescription, we study the damping of magneto-acoustic waves and the damping mechanisms of Alfvén waves, the turbulent and non-linear, as an additional heating source. We show that these damping mechanisms can increase the ionization fraction, making possible the presence of the MRI in a large part of the disk. In particular, the mechanism derived that couples the turbulent and non-linear damping mechanisms of Alfvén waves proved to be very efficient, generating temperatures almost one order of magnitude higher than those mechanisms considered independently.

## Chemical evolution of water in the protostellar environment

Jensen, Sigurd

Understanding the evolution of water during star formation, from the molecular cloud down to the circumstellar disk, is a central goal of astrochemistry.Open questions on this topic are how the water content is influenced by the local environment in which the protostar is formed, whether water is inherited directly from the molecular cloud and what role local processing during the cloud collapse plays for the water in the protoplanetary disk.We focus on the deuteration of water (HDO/H2O and D2O/HDO) as a tracer for the physical and chemical evolution of water around young protostars.We investigate the effects of the inhomogeneous star formation process by studying the formation of several hundred protostars in a realistic 3D MHD simulation of a molecular cloud from pc to tens of AU scales.For each of these protostars, we have large number of tracer particles available which track the gas flow providing the physical evolution of the material. On these particles, we evolve the chemical network from pre-collapse conditions down to the scales of the protostellar disk in a 3-phase model which includes both gas, surface and mantle species and track the buildup of ices species layer by layer.The theoretical results will be combined with incoming high-resolution ALMA observations of water and its isotopologues around young protostars. With the combination of an increased observational and theoretical sample we aim to pinpoint the important steps in the evolution of water and constrain the origin of water in the Solar System.

## The measurements of beam efficiency, size, and shape of TRAO 13.7-m Radio Telescope

Jeong, Il-Gyo

We introduce performance and capability of the 13.7-m Taeduk Radio Astronomy Observatory (TRAO) telescope. Recently, TRAO was  equipped with the new receiver, SEQUOIA-TRAO, consisting of high performing 16-pixel focal plane array with the operating frequency range from 86 to 115 GHz. The radome is the considerable factor that affects the frequency dependent efficiency of the telescope . The 30 years old radome that has been worn out went through weathering is switched to the new radome in 2017. In order to measure the beam size and efficiency of the TRAO, we executed the continuum observation of Jupiter at 86, 98, 110 and 115 GHz with the On-The-Fly mapping mode in 2016. Moreover, we repeated the continuum observation in order to determine the influence of the radome in 2017. The full width half maximum of the beam size were measured to be about 60’’ and 47’’ at 86 and 115 GHz. The measured aperture efficiencies are 31, 35, 39, and 36 % in 2016, and 43, 42, 37, and 33 % in 2017, respectively. The main-beam efficiencies are 37, 42, 49, and 46 % in 2016, and 45, 48, 46, and 41 % in 2017, respectively. We also present the molecular line spectra of each frequency toward the Orion-KL and IRC10216.

## A photometric study of KIC 8682849 showing strong variations in the period and light curve

Jeong, Min-Ji

We report a photometric study of KIC 8682849 based on the high precision data observed continuously for about 4 years by the Kepler mission. KIC 8682849 is a W UMa-type binary star with a short orbital period of 0.352 d. It shows strong variations of light curve as well as an anti-correlated pattern between the primary and secondary times of minima. Period-searches were tried to find any periodicities in the variations of light curve and the anticorrelated patterns. We found that both variations show to be quasi-periodic and have nearly the same period of about 77 days. Based on the results, a symmetric light curve mostly free from the variations of light curve and anti-correlation was chosen and solved with the 2015 Wison-Devinney binary model. It was found that KIC 8682849 is the over-contact binary system with an extremely low mass ratio and a deep fill-out factor. The rest asymmetrical light curves were modelled only with spot parameters to track the time-migrations of spot position on the surface of larger and hotter components. The modelled properties of the time-varying spots are discussed.

## CO molecular line observations of HII region G84.9+0.5

Jeong, Il-Gyo

We present the results of the multiple transitions of CO molecular line observations toward the Galactic HII region G84.9+0.5. The low transition 12CO and 13CO molecular line observations are executed with the Taeduk Radio Astronomy Observatory (TRAO) 13.7-m radio telescope in order to explore the distributions of molecular clouds and search for the star-forming activity along the H II region.  We mapped 20’ x 20’ area with On-The-Fly mapping mode of the TRAO to cover the whole area of H II region. Several molecular clumps are detected in the vicinity of the H II region, and the velocity component at ~-41 km/s these clumps seem to strongly correlated with the H II region spatially. The estimated kinematic distance toward the H II  region is about 5.5 kpc. Thus, 12CO J=3-2 molecular line observation was performed in order to investigate the spatial correlation between these clumps and the H II region G84.9+0.5. The observation results indicate that the molecular cloud distributions are well matched along the H II region identified as the distinct ring-like morphology with a small radius (~3'). The infrared images from Spitzer and Herschel clearly show the ring-like H II region shape and the point sources are associated with molecular dense clumps. At the northern part of the H II region, we were able to detect the broadened CO velocity profiles might imply the existence of the young stellar objects as well as the outflow feature. We show the detailed observation results and present the characteristics and properties of the HII region G84.9+0.5.

## NIR Color–Metallicity Relations and Color Distributions of Globular Cluster system in Elliptical Galaxy NGC 4649 with Subaru/MOIRCS

Jeong, Jong-Hoon

We present Subaru Near-Infrared (NIR) photometry for the globular cluster (GC) system in NGC 4649 (M60), the giant elliptical galaxy belonging to the Virgo cluster. NIR data are obtained in Ks - band with the Subaru/MOIRCS, and HST/ACS and Gemini/GMOS optical data available in the literature are used to investigate the origin of GC color bimodality in early-type galaxies. A clear bimodal color distribution is observed in the optical colors g475 – z850 and g'– i', and this bimodality is commonly considered as evidence for the presence of two GC subpopulations with different metallicities. By contrast, the more metallicity-sensitive Opt-NIR colors such as z850 – Ks and i'– Ks show a considerably weakened or no bimodality in their distributions. Furthermore, color–color relations of the optical and Opt-NIR colors for the NGC 4649 GC system exhibit a nonlinear feature. Our results support the recent claim that the optical color bimodality observed in GC systems of early-type galaxies is caused by the nonlinear nature of their color–metallicity relations.

## S-type planets formation in close binaries: scattering induced tidal capture of circumbinary planets

JI, Jianghui

Although several S-type and P-type planets in binary systems were discovered in past years, S-type planets have not yet been found in close binaries with a separation not more than 5 au. Recent studies suggest that S-type planets in close binaries may be detected using the current high-accuracy radial velocity (RV) and photometric measurements. However, current planet formation theories generally suggest that it is difficult for S-type planets in close binaries systems to form in situ. In this study, we extensively perform numerical simulations to explore the scenarios of planet-planet scattering among circumbinary planets and subsequent tidal capture in various binary configurations, to examine whether the mechanism can play a part in producing such kind of planets. The maximum capture probability is approximately %10, which can be comparable to the tidal capture probability of hot Jupiters in single star systems. The capture probability is related to the binary configuration, where a smaller eccentricity or a low mass ratio of the binary will lead to a larger probability of capture, and vice versa. Furthermore, we find that the S-type planets with retrograde orbits can be naturally produced during capture process. These planets on retrograte orbits can help us distinguish in situ formation and post-capture origin of S-type planet in close binaries systems. The forthcoming missions such as PLATO will provide the opportunity and feasibility to detect these planets. Our work provides several suggestions for selecting target binaries to search S-type planets in the near future according to the investigation.

## A Small UV mission CAFE for Warm Baryons in Nearby Universe

Ji, Li

We will present the current status of the on-going research project, a small UV mission CAFE both scientifically and technically. CAFE was proposed for UV line emission mapping for IGM and nearby galaxies, which will investigate those filaments connecting the galaxies and the large-scale structure of the Cosmic Web, and make the first maps of the three-dimensional structure of the dense part of the 104and 105K WHIM, and of the accretion and feedback flows around galaxies.

## The YSZ,Planck -YSZ,XMM scaling relation and its difference between cool-core and non-cool-core clusters

JIA, Shumei

We construct a sample of 70 clusters using data from XMM-Newton and Planck. YSZ,XMM is calculated by accurate de-projected temperature and electron number density pro?les derived from XMM-Newton. YSZ,Planck is the latest Planck data restricted to our precise X-ray size ?500. To study the cool-core in?uences on YSZ,Planck -YSZ,XMM scaling relation, we apply two criteria, limits of central cooling time and classic mass deposition rate, to distinguish cool-core clusters (CCCs) from non-cool-core clusters (NCCCs). We also use YSZ,Planck from other papers, which are derived from di?erent methods, to con?rm our results. The intercept and slope of the YSZ,Planck -YSZ,XMM scaling relation are A = -0.86±0.30, B = 0.83±0.06. The intrinsic scatter is sins = 0.14±0.03. The ratio of YSZ,Planck/YSZ,XMM is 1.03±0.05, which is perfectly agreed with unity. Discrepancies of YSZ,Planck -YSZ,XMM scaling relation between CCCs and NCCCs are found in observation. They are independent of cool core classi?cation criteria and YSZ,Planck calculation methods, although discrepancies are more signi?cant under the classi?cation criteria of classic mass deposition rate. The intrinsic scatter of CCCs (0.04) is quite small compared to that of NCCCs (0.27). The ratio of YSZ,Planck/YSZ,XMM for CCCs is 0.89±0.05, suggesting that CCCs YSZ,XMM may overestimate SZ signal. By contrast, the ratio of YSZ,Planck/YSZ,XMM for NCCCs is 1.14±0.12, which indicates that NCCCs YSZ,XMM may underestimate SZ signal.

## On the silicate crystallinities of oxygen-rich evolved stars and their mass-loss rates

Jiang, Biwei

For decades ever since the early detection in the 1990s of the emission spectral features of crystalline silicates in oxygen-rich evolved stars, there is a long-standing debate on whether the crystallinity of the silicate dust correlates with the stellar mass-loss rate. To investigate the relation between the silicate crystallinities and the mass-loss rates of evolved stars, we carry out a detailed analysis of 28 nearby oxygen-rich stars. We derive the mass-loss rates of these sources by modelling their spectral energy distributions from the optical to the far-infrared. Unlike previous studies in which the silicate crystallinity was often measured in terms of the crystalline-to-amorphous silicate mass ratio, we characterize the silicate crystallinities of these sources with the flux ratios of the emission features of crystalline silicates to that of amorphous silicates. This does not require the knowledge of the silicate dust temperatures, which are the major source of uncertainties in estimating the crystalline-to-amorphous silicate mass ratio. With a Pearson correlation coefficient of -0.24, we find that the silicate crystallinities and the mass-loss rates of these sources are not correlated. This supports the earlier findings that the dust shells of low mass-loss rate stars can contain a significant fraction of crystalline silicates without showing the characteristic features in their emission spectra.

## Binary evolution and double sequences of blue stragglers in globular clusters

Jiang, Dengkai

Double sequences of blue stragglers in the color-magnitude diagram of globular clusters are important to study the formation mechanisms of blue stragglers. We study the formation of blue stragglers from binary evolution. We find the location of a blue-straggler binary produced by mass transfer in binary systems depends on the contribution of the mass donor to the total luminosity of the binary, because two components of this binary system cannot be distinguished. In the blue sequence, the blue-straggler binaries have a blue straggler orbiting a cool white dwarf. However, the red sequence include blue-straggler binaries that are experiencing mass transfer, or just terminating mass transfer, and the blue-straggler binaries that the blue stragglers have evolved away from the blue sequence. We suggest that mass transfer in binary systems can contribute to the blue stragglers in both of the sequences in globular clusters.

## Application of 1-m class telescopes network in time domain astronomy

Jiang, Xiaojun

We collect the specifications, performance, and locations of the 1-m class telescopes in China. We further investigate the scientific goals suitable for the network/clusters of these telescopes, including time series observations, coordinated photometric and/or spectroscopic observations using multiple telescopes in different observation modes at the same or different sites. The strategy and solution for the coordinated observations is given.

## OBSERVATIONS OF 01 SEPTEMBER 2016 ANNULAR SOLAR ECLIPSE FROM TANZANIA

JIWAJI, NOORALI

The major astronomical event of an Annular Solar Eclipse that crossed through the heart of Africa on September 01, 2016 was used as an outreach, educational, and scientific opportunity in Tanzania.  We present the challenges of organising, funding and reaching the population and educating the public as well as students in schools across the country.  We also present findings of global solar radiation and temperature changes monitored during the eclipse.  Results show a practically night sky situation during full annularity and a nearly 4oC drop in air temperature at full eclipse.

## Global distribution of far-ultraviolet emission from the highly ionized gas in the Milky Way

Jo, Young-Soo

One of the keys to interpreting the characteristics and evolution of interstellar medium in the Milky Way is to understand the distribution of hot gas (105–106 K). Gases in this phase are difficult to observe because they are in low density and lack of easily observable tracers. Hot gases are observed mainly in the emission of the FUV (912—1800 Å), EUV (80—912 Å), and X-rays (T>106 K) of which attenuation is very high. Of these, FUV emission lines originated from high-stage ions such as O VI and C IV can be the most effective tracers of hot gases. To determine the spatial distribution of O VI and C IV emissions, we have analyzed the spectra obtained from FIMS (Far-ultraviolet IMaging Spectrograph), which covers about 80 percent of the sky. The hot gas volume filling factor, which varies widely from 0.1 to 0.9 depending on the supernova explosion frequency and the evolution model, has been calculated from the O VI and C IV maps. The hot gas generation models has been verified from the global distribution of O VI and C IV emissions, and a new complementary model has been proposed in this study.

## The HI Neighborhoods Around STARBIRDS

Johnson, Megan

Starbursts are finite periods of intense star formation (SF) thatcan dramatically impact the evolutionary state of a galaxy.Recently, published results have redefined both the duration and spatialextent of starbursts in dwarf galaxies to be longer and more distributedthan previously thought, with star formation efficiencies (SFEs) comparableto spiral galaxies.  The contrast between these SFEs and those typical ofnon-bursting dwarfs highlights the inconsistencies between two SF modes thatcan operate in low-mass galaxies.  These inconsistencies might beexplainable if the starburst mode of SF is externally triggered bygravitational interactions with other nearby systems.  We present new,sensitive neutral hydrogen observations of 18 starburst dwarf galaxies,which are part of the STARburst IRregular Dwarf Survey (STARBIRDS) and eachwere mapped with the Green Bank Telescope (GBT) and/or Parkes Telescope inorder to study the low surface brightness gas distributions, a common tracer for tidal interactions.

## Planetary cores, their energy flux relationship, and its implications

Johnson, Prof. Fred M.

Integrated surface heat flux data from each planet in our solar system plus over 50 stars, including our Sun, was plotted against each object’s known mass to generate a continuous exponential curve at an R-squared value of 0.99. The unexpected yet undeniable implication of this study is that all planets and celestial objects have a similar mode of energy production. It is widely accepted that proton-proton reactions require hydrogen gas at temperatures of about 15 million degrees, neither of which can plausibly exist inside a terrestrial planet. Hence, this paper proposes a nuclear fission mechanism for all luminous celestial objects, and uses this mechanism to further suggest a developmental narrative for all celestial bodies, including our Sun. This narrative was deduced from an exponential curve drawn adjacent to the first and passing through the Earth’s solid core (as a known prototype). This trend line was used to predict the core masses for each planet as a function of its luminosity.

## Stellar Activity Indicators in the CARMENES Sample

Johnson, Erik

Stellar activity has long been a source of irritation for exoplanet surveys as the radial velocity signal from the stellar activity is on the same order of magnitude as that from terestrial planets in their habitable zones. This is especially true for the M-type stars in the CARMENES survey. Statistical methods can alleviate some of the effects but require extensive-and costly- data sets to work. Understanding and relating the signals of stellar activity through chromospheric and photospheric indicators is vital to deconvolving the planetary radial velocity signal from the stellar activity signal.

## The Influence of Chemical Composition on Planetary Upper Atmospheres and Atmospheric Losses

Johnstone, Colin

The thermal and chemical structures of the upper atmospheres of planets are very important for determining how quickly atmospheric gas is lost to space. These structures are determined by a range of processes, including heating by stellar radiation, especially in X-ray and UV wavelengths, and cooling by IR radiation from molecules such as carbon dioxide. The importance of each of the relevant mechanisms depends sensitively on the atmospheric composition. In this talk, I will discuss different atmospheric chemical compositions, and how they influence the atmospheric heating and cooling. I will link this to atmospheric loss mechanisms and long term atmospheric evolution.

## Dust producing AGB stars in the Metal-poor, Dwarf Irregular Galaxies Sextans A and Leo A

Jones, Olivia

We present JHK s observations of the metal-poor ([Fe/H] < -1.40) dwarf-irregular galaxies, Leo A and Sextans A, obtained with the WIYN High-resolution Infrared Camera at Kitt Peak. Their near-IR stellar populations are characterized by using a combination of color–magnitude diagrams and by identifying long-period variable stars. We detected red giant and asymptotic giant branch stars, consistent with membership of the galaxy’s intermediate-age populations (2–8 Gyr old). Matching our data to broadband optical and mid-IR photometry, we determine luminosities, temperatures, and dust-production rates (DPR) for each star. We identify 32 stars in Leo A and 101 stars in Sextans A, confirming that metal-poor stars can form substantial amounts of dust. We also find tentative evidence for oxygen-rich dust formation at low metallicity, contradicting previous models that suggest oxygen-rich dust production is inhibited in metal-poor environments.  The majority of this dust is produced by a few very dusty evolved stars and does not vary strongly with metallicity

## Characterizing SZ and X-ray Selected Samples of Clusters of Galaxies

Jones, Christine

Using Chandra observations, we compare the cluster masses and fractions of cool core clusters in X-ray and SZ selected cluster samples.   In particular, we analyzed 164 clusters (z<0.35) from the Planck Early SZ sample and 100 clusters from a flux-limited X-ray sample (z<0.3).  We find that cluster mass determinations derived from SZ or X-ray observations are in good agreement (Andrade-Santos et al. 2018).  We also find, using four different metrics to identify cluster cool cores,  that for each metric,  the sample of X-ray selected clusters contains a significantly larger fraction of cool core clusters, compared to the SZ sample.  In particular, the measured fraction of cool core clusters in the X-ray sample ranges from ~40 to 60%, depending on the particular metric used to identify cool cores, while the fraction of cool core clusters in the SZ sample ranges from ~30 to 40% (Andrade-Santos et al. 2018).  Thus X-ray flux-limited cluster samples, compared to the approximately mass-limited SZ sample, are overrepresented with cool-core clusters. We describe a simple model that uses the excess luminosity of cool-core clusters, compared to non-cool-core clusters at fixed mass, to successfully predict the observed fraction of cool-core clusters in X-ray-selected samples. In addition, we find that cluster masses derived from Chandra observations agree well with Planck SZ masses (Andrade-Santos et al. 2019).

## 2D metallicity gradients and how they depend on substructures in MaNGA galaxies

Jones, Amy

Many galaxies have a metallicity gradient, however there is a large scatter about the slope of this gradient.  Typically the galaxy is azimuthally averaged to look only at the 1D metallicity profile as a function of radius.  With IFU observations, we no longer need to azimuthal average, but instead can use the 2D metallicity map to describe metallicities in galaxies. With SDSS IV MaNGA observations, we can disentangle the scatter in the 1D profile by measuring metallicity gradients along certain substructures within the galaxies, e.g. spiral arms and bars.  By looking at the gradients along the structures, we hope to minimize the scatter and compare these different gradients.  We will use the full 2D information to find quantitative parameters, such as asymmetry, M20, and MID diagnostics, to describe the metallicity distribution within galaxies and see how these correlate with other galactic properties and structure.

## Turbulent Generation of Galaxy Cluster Magnetic Fields

Jones, Thomas

Observations, and especially radio observations, reveal that microGauss-strength magnetic fields commonly pervade ICMs. Although the bulk dynamical stresses of those fields are probably sub-dominant to other forces, the fields should still play critical roles in ICM behaviors through microphysics, energy transport and dissipation processes. Largely independent of the sources of ICM seed magnetic fields, the extent and magnitude of the fields almost certainly depend on amplification and distribution by ICM turbulence. The effectiveness of turbulence in this context depends, in turn, on the strength, distribution, duration and character of the turbulence during cluster formation and evolution. In this presentation I will outline results from our simulation studies of MHD turbulence and cluster formation dynamics addressing these issues. I will emphasize the importance of turbulence "character", as well as its distributions in space and time, and also stress the implications to ICM physics of the observed ICM magnetic field properties.This work is supported at the University of Minnesota by the US National Science Foundation and the University of Minnesota Supercomputing Institute.

## SN 1987A: The Formation and Evolution of Dust in a Supernova Explosion

Jones, Olivia

From Supernova to Supernova Remnant, SN 1987A, has given us a unique opportunity to study the mechanics of a supernova explosion and now to witness the birth of a supernova remnant. With JWST, we wish to understand how massive stars age and explode, how their ejecta forms dust and molecules and how the blast wave from their violent explosion affects their surroundings. In this talk, I will describe the scientific goals of the joint nine hour program between the MIRI European Consortium and Meixner's US MIRI Science Time allocation to capture the time evolution of SN1987A using JWST MIRI imaging, MRS spectroscopy and NIRSpec IFU spectroscopy. These will provide key emission line diagnostics and dust feature and continuum measurements of SN 1987A.The central stellar ejecta of SN 1987A is surrounded by a ring of progenitor gas and dust that is being shocked by the blast wave of the explosion. A large quantity (0.4-0.7 M) of dust in the stellar ejecta has an unknown composition and our MIRI observations may provide the first constraints through the imaging and MRS spectroscopy. Both the MRS and NIRSpec IFU spectroscopy will measure key shocked line diagnostics that will constrain the shock physics as well as the elemental abundances in both the ring and the stellar ejecta.

## Towards a better scattered moonlight model and aerosol extinction determination at Cerro Paranal

Jones, Amy

Estimating the sky background is critical for ground-based astronomical research.  In the optical, scattered moonlight dominates the sky background, when the moon is above the horizon.  The most uncertain component of a scattered moonlight model is the aerosol scattering.  The current, official sky background model for Cerro Paranal uses an extrapolated aerosol extinction curve.  With a set of X-Shooter sky observations, we have tested the current model as well as determined the aerosol extinction from UV to NIR.  These observations were taken of plain sky, during three different lunar phases, and at six different angular distances from the moon for each night/lunar phase.  Using a set of models with varying aerosol distributions to compare with the observations, we found the most likely aerosol extinction curves, phase functions, and volume densities for the three nights of observations.  While there were some degeneracies in the aerosol scattering properties, in general the current model had significantly less coarse particles compared to the favored volume densities from the X-Shooter data.  This affects the phase function by being more peaked at small angular distances.  Also the extinction curves flatten towards redder wavelengths and are overall less steep compared to the extrapolated curve used in the official model.  Overall, the current model does reproduce the observations for average conditions decently well.  For the three nights of sky observations, the aerosol distributions differed reflecting the changes in atmospheric conditions and aerosol content, which is expected.  These changes among the three nights seemed to correlate with the atmospheric conditions recorded at the site.  Using sky observations and the sky background model is a unique way to probe the aerosol content of the atmosphere.

## SDSS efforts on inclusion for bridging different communities

Jones, Amy

The Sloan Digital Sky Survey (SDSS) IV is an international astronomy collaboration that has been in the fore-front of addressing issues of inclusivity within the collaboration.  Many of the things learned in SDSS can be applied to IAU activities and efforts.  SDSS IV originally created two committees, one focused on women and the other on minorities, and two years ago these joined to form COINS, the committee on inclusion in SDSS.  Part of the charge is to conduct a yearly or bi-yearly demographics survey to asses the inclusiveness within SDSS.  To help increase minority participation within SDSS and astronomy, we had the FAST (faculty and student teams) Initiative and REU (research experience for undergraduates) programs.  Additionally, there are many efforts to help younger members feel welcome and participate, currently with a focus at the collaboration meetings.  We have drafted several documents, including how to make a meeting more accessible and inclusive, best practices regarding code of conduct, best practices for running telecons, and meeting chairing guidelines.  I would like to share what has been successful for SDSS which would be useful for the IAU and bridging different communities.

## Using Inhomogeneous Chemical Evolution to Model Dwarf Galaxies

Jordan, Chris

We use an inhomogeneous chemical evolution (i-GEtool) code to model the dwarf spheroidal galaxy, Draco. Using i-GEtool as opposed to traditional chemical evolution models allows a natural dispersion to occur within the output data, thus mimicking observations. We tune our model to simulate the Draco system using the metallicity distribution function and star formation history. We investigate the alpha-element abundance distributions, comparing and contrasting different stellar yields to find a best fit to observational data. Lastly we examine methods used for calculating gas outflow in models.we confirm that the use of different stellar yields sets can change GCE results. For instance, the NuGrid yield set has problems reproducing the high [alpha/Fe] observations whereas the yields from do not reproduce the low [alpha/Fe] results. We use a new method in inhomogeneous codes to model outflows, allowing supernovae type-II to expand beyond the radius of Draco, making outflows self-consistent and more similar to current hydrodynamic models. Our outflow method was found to imply a high ratio of star formation rate to outflow rate, i.e. mass-loading, factor of ~15.

## Internal calibration of the spectrophotometry in Gaia mission

Jordi, Carme

Gaia space mission includes two slitless low-resolution spectrographs (one blue and another one red) aimed to parameterize the observed sources. The focal plane includes 7 CCDs for each of the spectrographs to acquire the observations. Gaia observes simultaneously with two telescopes. The Gaia spectra will be part of the next Data Release 3.The aim of the talk is to show the current approach for the internal self-calibration of all the acquired observations in order to define a mean instrument from the two fields of view and across the focal plane.

## Spectroscopic binaries among AGB stars

Jorissen, Alain

Very few spectroscopic binaries hosting an AGB component are known so far. We will present a few long-period binaries discovered with the HERMES spectrograph mounted on the Mercator telescope at the Roque de los Muchachos Observatory (La Palma). These discoveries open interesting prospects for diagnosing the interaction of the AGB wind with the companion. A few specific cases will be discussed.

## OH maser structures in the molecular cloud W49N.

Juarez, Mariana

W49N is part of the Giant Molecular Cloud (GMC) W49A, a high-mass star forming region, which is located near the galactic plane. W49A has been observed at different wavelengths, as millimeter and radio wavelengths, finding dozens of HII regions and many compact cores, many of which are at W49N. They indicate the presence of newly born high mass stars and protostars. This star forming region is one of the most efficients in our galaxy.The processes of high mass stars still have many caveats. For this reason, the study of W49N is of great importance. In particular, the identification of spatial structures, can give clue information on the ongoing processes as accretion and outflows and on their physical conditions. All these information can be used as probes of different models of high mass star formation.OH masers at 1612, 1665 and 1667 at RCP and LCP observed with the VLBA are analyzed in this work. We found a velocity gradient of the maser spots.  Also, large velocity dispersions of some groups of spots, that are close in distance, is observed. The parameters of the groups of these OH masers are being studied to evaluate their possible kinematics. For some of these groups, it is found that, their velocity dispersion seem to be due to the local kinematics rather than to global or turbulent motions.

## Use of Astronomy to Motivate the Girl Child into Science Related Careers

Jurua, Edward

The government of Uganda has a policy to improve the number of female students in tertiary institutions. This has motivated very few female students into science related programmes compared to the humanities in tertiary institutions. In the case of Mbarara University of Science and Technology, more male students are enrolled at undergraduate annually than the female students. This has a direct effect on the number of female students continuing to postgraduate studies in science related programmes. This could be due to socio-cultural reason. In addition, there are negative influences from the society, with the believe that science careers are meant for the male gender but not the female gender. We used Astronomy outreach to girls’ secondary schools to motivate the female students into the sciences.  In this paper, the use of astronomy to motivate and encourage the girl child into science related programmes in tertiary institutions in Uganda is discussed.

## Red Giant Star KIC 5110738 in the Kepler Open Cluster NGC 6819

Jurua, Edward

The Kepler Input Catalogue (KIC) misclassified a number of red giant stars as sub giants. This could have resulted from the large uncertainties in the KIC surface gravities. This resulted in 1523 stars which were recently classified red giant stars.  The cluster membership of the 1523 red giant stars was determined using age, distance modulus, and variation of colour magnitude with large frequency separation. We found that only one star is a member of NGC 6819.

## The dynamical impact of satellite galaxies on the Milky Way disc

Just, Andreas

We investigated the interaction of dark matter (DM) subhaloes on the thin disc of Milky Way-like host galaxies by high-resolution re-simulations combining the statistical properties of DM halos from the Aquarius simulations with a live host galaxy in dynamical equilibirum. We have shown that the contribution of DM subhalos to the dynamical heating of the inner disc of the Milky Way is not dominant. However, the impact of DM haloes with a few billion solar masses on disc perturbations like the bar, vertical wiggles and warps is significant. These DM intruders are not able to force a bar to form, but they can trigger or delay bar formation by up to a Gyr, if the galaxy becomes bar unstable. Consequently, from the existence of a (even young) bar one cannot infer a recent interaction event with a satellite galaxy. In contrast, vertically oscillating ring-like wiggles as observed recently in the Milky Way, have a lifetime of roughly 1 Gyr and thus point to a recent pertubation event. Warps of the outer disc survive for a few Gyr or even longer and serve as a cumulative measure of past harassement or merger events of satellite galaxies. The dynamics of the impact of DM subhaloes with respect to the formation and evolution of bars, wiggles and warps will be discussed.

## ALMA spectrum of the extreme OH/IR star OH26.5+0.6

Justtanont, Kay

We present ALMA band 7 data of OH 26.5+0.6 in band 7, resolving the CO J=3-2 emission which shows a compact core (FWHM = 0.6 arcsec), surrounded by tenuous envelope which extends out to 4-5 arcsec where CO is photodissociated. The circumstellar envelope also exhibit  a number of emission lines due to metals, e.g., NaCl and KCl. A lack of C$^{18}$O is expected but a nondetection of C$^{17}$O is puzzling given the strength of H$_{2}$^{17}$O from the Herschel spectrum of the star. However, a line associated with Si$^{17}$O is seen which may be indicative in molecular formation processesin envelope of extreme OH/IR stars. We also report a detection of the gas-phase emission line of MgS J=21-20. MgS dust is found exclusively in C-rich circumstellar environment and is thought to be the carrier of the 30$\mu\$m dust feature. ALMA spectrum of this object reveals intriguing features which may be used to investigate chemical processes and dust formation during a high mass-loss phase.

## Dust emission and polarisation in the massive star-forming filament G35.39-0.33

Juvela, Mika

G35.39-0.33 is a massive (~5000 MSun) filamentary cloud at a distance of 2.9 kpc. It has a number of low-luminosity infrared sources and potentially prestellar massive cores but still appears to be in an early stage of its star formation activity. We have used JCMT POL-2 850 µm observations and Planck 353 GHz measurements to study dust emission and polarisation in the G35.39-0.33 field. The relationships between the magnetic field geometry, grain alignment, and polarisation fraction were examined with radiative transfer modelling.The G35.39-0.33 cloud exhibits large values of submillimetre dust opacity and opacity spectral index, both typical of very dense clouds. Planck data reveal an almost uniform polarisation fraction and a field direction that is at an oblique angle relative to the main cloud. In SCUBA-2 observations, the magnetic field is mostly perpendicular to the filament but at one end turns parallel to it. There is no contradiction because the SCUBA-2 measurements are not sensitive to the large scale field. The polarisation fraction in the filament is of the order of p=1-2%. The decrease of p as a function of column density is partly caused by noise, with a possible contribution from the filtering of the extended emission. The data are in agreement with models where grain alignment is lost at densities above ~104 cm-3. The agreement with simulations employing radiative torques alignment is only approximate but strong conclusions are precluded by the uncertainty of the 3D field geometry and the spatial filtering of the ground-based observations.The presentation is given on behalf of the JCMT Large Program SCOPE (PI T. Liu).

## Evolution of Milky Way angular momentum: comparison of the Newtonian gravity with DM and non-Newtonian gravity without DM

Kacala, Ivan

Evolution of Milky Way angular momentum: comparison of the Newtonian gravity with DM and non-Newtonian gravity without DMIvan Kacala, Roman Nagy, Jozef KlackaDepartment of Astronomy, Physics of the Earth and MeteorologyFaculty of Mathematics, Physics and Informatics, Comenius UniversityMlynská dolina F1, 842 48 Bratislava, Slovak RepublicA standard approach to examination of orbital evolution of stars in the galactic disk and related evolution of the galactic angular momentum considers Newtonian gravity and the spherical halo of dark matter. In our contribution, we compare this standard approach with a new approach considering modified Newtonian dynamics / gravity based on observational results from the work by McGaugh et al. (2016) and the spherical halo of dark matter is not considered. We trace distribution of angular momentum of stars in the Milky Way galaxy for the two approaches described above by simulating motion of more than 103 stars. The models of the galactic structures (central bar, galactic disk and spiral arms) used in our simulations are in accordance with observed properties of the Milky Way, e. g., Freudenreich (1998), Antoja et al. (2011), Klacka et al. (2012). We find that the distribution of angular momentum in the new approach corresponds, approximately, to the conventional distribution of angular momentum, if the standard Newtonian approach is considered.References:Antoja T., Figueras F., Romero-Gómez M., Pichardo B., Valenzuela O., Moreno E.: 2011, Understanding the spiral structure of the Milky Way using the local kinematic groups. Mon. Not. R. Astron. Soc. 418, 1423Freudenreich H. T.: 1998, A COBE model of the galactic bar and disk. Astrophys. J. 492, 495Klacka J., Nagy R., Jurci M.: 2012, Radial migration of the sun in the galactic disc. Mon. Not. R. Astron. Soc. 427, 358McGaugh S. S., Lelli F., Schombert J. M.: 2016, The Radial Acceleration Relation in Rotationally Supported Galaxies. Phys. Rev. Lett. 117, 201101