Focus Meeting 11 - Abstracts
Technologies Developed and Challenges Overcome Along the Journey to the James Webb Space Telescope
Smith, Eric
In 1995, scientists asked NASA for an infrared telescope to go far beyond what Hubble can show us, looking at everything from the first stars, galaxies, and black holes, to objects like planets and dust clouds that are too cool to emit visible light, to exoplanets, to planets, comets, asteroids, and satellites throughout our solar system. NASA, working with international partners ESA and CSA, responded with the James Webb Space Telescope, far larger and more powerful than any space telescope before. I will discuss technologies developed for, and challenges overcome by the program thus far as we near the final steps of integration and testing.
NIRCam for JWST: New Science Near and Far
Rieke, Marcia
NIRCam has been built with deep surveys as a prime design driver, and the resulting camera will be superb for such observations. These same design criteria, with the addition of other components, have led to a NIRCam that ensures stunning capabilities in many other areas such as exoplanet studies where NIRCam can observe transits spectroscopically and architectures of exoplanet systems via coronagraphy with NIRCam's complement of 3 to 5 micron filters providing diagnostics of exoplanet atmospheres. NIRCam's medium and narrow filters provide new capabilities for studying obscured star formation and ices.
Studying the evolving interstellar medium of galaxies with JWST
Kemper, Ciska
In this talk, I will review outstanding questions on the properties andthe evolution of the interstellar medium of galaxies, including ourown Milky Way, that can and will be addressed with the JWST in the comingyears. I will build on what we have learnt from previous facilities,in particular the Spitzer Space Telescope; in particular, results from theSurveying the Agents of Galaxy Evolution (SAGE) survey of the MagellanicClouds will be used to define key questions for the evolution of theinterstellar medium of galaxies.
Science with NIRISS: The Near-Infrared Imager and Slitless Spectrograph
Willott, Chris
The NIRISS instrument on JWST provides imaging and spectroscopy from 0.6 to 5 microns. I will describe science applications of the 4 observing modes of NIRISS, from characterizing extrasolar planets that could host life to understanding the formation of galaxies prior to cosmic reionization.
JWST Commissioning from Launch to Science Observations
McElwain, Michael
The James Webb Space Telescope (JWST) is a large, 6.5 m segmented aperture telescope equipped with near- and mid-infrared instruments that will observe over a wavelength range of 0.6-28.4 microns. The near-infrared instruments are passively cooled to ~40 K by a 5-layer sunshield while the mid-infrared instrument is actively cooled to 7 K. The goal of JWST commissioning is to provide a timely preparation of the Observatory for science programs, which drives the entire commissioning plan. The JWST is stowed for launch and must carry out orbital insertion maneuvers to its final orbit at L2. While en route to L2, the JWST will maintain communications via NASA's Deep Space Network and make Observatory deployments to enable the passive cooling of the telescope and the science instruments. When cold, the segmented telescope will be aligned by identifying segments, providing wavefront control at the segment-level, co-phasing segments, and correcting the image quality over the large focal plane feeding the science instruments. Finally, the science instruments will execute a series of activities aimed at confirming functionality and calibrating for science. The entire commissioning phase is scheduled to take less than 6 months. Commissioning will be completed by the JWST mission operations team, which is comprised of the international partners from NASA, ESA, and CSA, the aerospace industry partners such as Observatory contractor Northrop Grumman Aerospace Systems, and the science and mission operations center at the Space Telescope Science Institute.
The JWST Mid Infrared Instrument (MIRI) and the science it enables
Wright, Gillian
I will provide an overview of the James Webb Space Telescope MIRI instrument and its scientific capabilities. The only mid-infrared instrument for JWST, MIRI provides diffraction limited imaging, low resolution spectroscopy, coronagraphs and moderate resolution integral field spectroscopy at wavelengths ranging from 5 to 28um. These capabilities coupled with unprecedented sensitivity and spatial resolution compared to previous missions will enable a broad range of science. I will discuss examples from the early science plans, showing how MIRI will be used to address topics from star and planet formation, to the earliest galaxies in the Universe
The Status and Expected Performance of the James Webb Space Telescope
Gardner, Jonathan
The James Webb Space Telescope currently consists of two parts. The Instruments have been integrated onto the telescope, and have successfully undergone a full end-to-end optical cryogenic vacuum test. The spacecraft and sunshield have been integrated together; by the time of the conference they will be completing a suite of acoustic, vibration and vacuum testing. The telescope will be integrated onto the spacecraft and will undergo final observatory-level testing in preparation for launch. I will review the expected performance of the observatory. By the time of the conference, the full Cycle 1 program, including the Early Release Science, Guaranteed Time Observations and General Observer programs are expected to be announced. I will show recent progress and the current status of the observatory and show how you can keep up with progress as the project proceeds to launch, commissioning and scientific operations.
JWST science prospects: a pre-launch taste
van Dishoeck, Ewine
JWST promises to examine every phase of cosmic history: from the epoch of re-ionization after the Big Bang to the formation of galaxies, stars, and planets, the atmospheres of exoplanets and the evolution of our own solar system. Its leap in sensitivity, angular resolution and broad wavelength coverage from optical to mid-infrared compared with other missions will ensure major steps forward in many areas. Here a brief "taste" of future JWST science will be presented, by highlighting a number of specific examples from each of the science areas. Synergies with other major facilities will be emphasized.
A JWST Early Release Science Program to Directly Image Extrasolar Planetary Systems
Hinkley, Sasha
In preparation of the launch of JWST a broad range of proposals have been selected under the Director’s Discretionary Early Release Science Program (DD-ERS) with the primary goal of rapidly producing representative datasets across the modes of JWST within the first few months of operation. Our accepted program, “High Contrast Imaging of Exoplanets and Exoplanetary Systems with JWST”, has been awarded ~52 hours of time and will perform: a) coronagraphic imaging of a newly discovered exoplanet companion, and a well-studied circumstellar debris disk with NIRCam & MIRI; b) spectroscopy of a wide separation planetary mass companion with NIRSPEC & MIRI; and c) deep aperture masking interferometry with NIRISS. These observations have been tailored to the specific goals of our program: 1) generate representative datasets in modes to be commonly used by the exoplanet and disk imaging communities; 2) deliver science enabling products to empower a broad user base to develop successful future investigations; and 3) carry out breakthrough science by characterising exoplanets for the first time over their full spectral range from 2-28 microns, and debris disk spectrophotometry out to 15 microns sampling the 3 micron water ice feature. We present a summary of these observations and our planned science enabling products in order to inform the community ahead of the launch of JWST.
The JWST near-infrared spectrograph NIRSpec
Alves de Oliveira, Catarina
The near-infrared spectrograph NIRSpec is one of four instruments aboard the James Webb Space Telescope (JWST). NIRSpec is developed by ESA with AIRBUS Defence & Space as prime contractor. It offers seven dispersers covering the wavelength range from 0.6 to 5.3 micron with resolutions from R~100 to R~2700. Using an array of micro-shutters, NIRSpec will be capable of obtaining spectra for over 100 objects simultaneously. It also features an integral field unit with a 3 by 3 arcseconds field of view, and various slits for high contrast spectroscopy of individual objects and time series observations, including those of transiting exoplanets. We will provide an overview of the capabilities and performances of the three observing modes of NIRSpec, and how these are linked to the four main JWST scientific themes.
Probing the Lowest-Mass Free-Floating Objects with JWST: GTO Program and Beyond
Jayawardhana, Ray
How far down in mass the stellar initial mass function (IMF) extends is a fundamental, unresolved question in astrophysics. The shape of the IMF at the lowest masses will not only establish the boundary between objects that form ‘like stars’ and those that form ‘like planets’, but also distinguish among competing theoretical models for the origin of brown dwarfs. Thanks to extensive surveys by us and others, the IMF is now reasonably well characterized in several nearby star-forming regions down to about 10 Jupiter masses, but not below. Our approved GTO program with NIRISS on the JWST aims determine whether there is a substantial population of hitherto undetected 1-5 Jupiter mass objects, possibly formed in protostellar disks and subsequently ejected. We plan to use NIRISS in the WFSS mode to survey a nearby young cluster to unprecedented depth, in order to (1) establish firmly the shape of the IMF below the Deuterium-burning limit, (2) investigate the fragmentation limit for ‘star-like’ formation, and (3) quantify the population of isolated planetary-mass objects. Our observations of NGC 1333 will not only identify and confirm objects down to 1-2 Jupiter masses, but also provide a first estimate of their temperature, and thus mass. Follow-up high- resolution spectroscopy with NIRSpec could improve temperature/mass estimates, derive C/O ratios to trace the formation mechanism, look for accretion features, and test atmosphere models. Multi-band MIRI photometry of planetary-mass objects could probe the presence and characteristics of dusty disks in their midst.
Star formation in the Local Group with NIRSpec and NIRCam
De Marchi, Guido
I will present a NIRSpec GTO programme showcasing the multi-object spectroscopy capabilities of NIRSpec for stellar studies. We will obtain medium- and high-resolution spectra of hundreds of known pre-main sequence (PMS) stars with different ages hosted in massive starburst clusters in the Galaxy and Magellanic Clouds. These PMS stars were identified from HST photometry as objects with strong Hα excess emission (EW > 10Å). Each cluster contains about 500–1000 such PMS stars in a typical 3’x3’ field, thereby guaranteeing optimal filling of the NIRSpec Micro-Shutter Array. The ultimate scientific goal is to understand the very nature of the mass accretion process, and how the corresponding infall of gas from the circumstellar disc onto the star depends on the mass, age, and metallicity of the PMS object. This study is unique, since spectroscopic studies of PMS objects so far are limited to the solar neighbourhood and no information exists for massive starburst clusters and for non-solar metallicity. In particular, our observations will sample multiple hydrogen recombination lines (Paα, Brβ, Brγ), and from their intensities and profiles we will extract quantitative information on the nature, excitation, and kinematics of the infalling gas. I will also show how the parallel observations with the NIRCam instruments will allow us to discover new PMS stars and to measure their mass accretion parameters through narrow-band NIR photometry, which will be in turn directly calibrated by the NIRSpec spectroscopy. This study is bound to have important implications and set firm foundations for our understanding of the star formation process in both the local and the early Universe.
Towards a Sub-Gyr Age of the Ancient Globular Cluster M92 with JWST
Kalirai, Jason
Messier 92 is the nearest system to the Sun that represents a truly ancient and metal-poor stellar population. High precision visible light photometry of the globular cluster consistently shows it to be a 13 Gyr population. In our James Webb Space Telescope Early Release Science (ERS) Program, "The Resolved Stellar Populations ERS Program", we will obtain exquisite near-infrared photometry of the cluster down to well below the newly discovered main-sequence "kink" feature, below which lower-mass and cooler M dwarfs become bluer in the infrared colors. By modeling the stellar populations on this infrared plane, we can remove degeneracies between distance, reddening, and metallicity and establish the most accurate age of the globular cluster to date. For M92, this measurement sets a new limit on when the earliest baryonic structure formation began in the Milky Way galaxy. In this presentation, we will demonstrate the power of infrared diagnostics to establish globular cluster properties based on state-of-the-art Hubble Space Telescope WFC3/IR observations, and motivate our new ERS program.
Finding Embedded AGN with MIRI
Rieke, George
I will illustrate the breakthroughs enabled by the Mid-Infrared Instrument (MIRI) on JWST, through the example of identifying embedded active galactic nuclei (AGN). Multiple approaches have been used to find AGN, with significant overlap in the samples identified. However, some objects meet one criterion but not others. A critical example is that power law spectra and other clues in the infrared reveal AGN candidates not detected in the deepest X-ray surveys. Even the hard X-rays detected with NuStar fail to find some AGN where we expect them. These results and theoretical models imply that AGN are likely to be hidden during their early development in extremely dense and heavily obscuring interstellar clouds of gas and dust. MIRI can find these hidden AGN in multiple ways. First, MIRI and NIRCam multiband photometry can identify galaxies where the spectral minimum around 4.5 microns (the longest wavelength where stellar photosphere emission dominates over aromatic bands) is filled in by emission by an embedded AGN. This approach is similar to the color-color diagrams developed for Spitzer IRAC and WISE photometry, but much more powerful because the MIRI bands allow this minimum to be isolated cleanly and uniformly for 0 < z < 2.5. Second, using the MIRI IFU/MRS provides a new level of sensitivity to high-excitation fine structure lines, particularly [Ne VI] at 7.65 microns, unique because of its high ionization potential (158 eV), high critical density, and availability to MIRI out to z = 2.5. Third, even the most deeply embedded AGN such as Mkn 231 heat the surrounding dust and much of their energy emerges as a mid-infrared pseudo-blackbody. This emission can be identified through its dilution of the stellar CO fundamental absorption bands (4.5 – 4.75 microns, within the MIRI range for z > 0.03), and of the aromatic features. The latter two approaches are enhanced by imaging with the IFU, probing whether the AGN signature is confined tightly on the galaxy nucleus.
The Star Formation History and assembly of galaxies at z=4-7 probed by CEERS and the GTO MIRI Deep Survey (MDS) and parallels
Pérez-González, Pablo
I will present a project to study the Star Formation History and assembly of high redshift galaxies using CEERS data as well as the JWST Guaranteed Time observations awarded to the MIRI European Consortium Science Team.The Cosmic Evolution Early Release Science Survey (CEERS) is an observing programme selected for execution during the Early Release Science phase of observations on the James Webb Space Telescope. The MIRI Deep Survey (MDS) will obtain ultra-deep imaging and spectroscopy not only with MIRI, but also with NIRCam and NIRISS, providing unprecedented and uniquely deep data during the first year of the JWST mission.Among the many science topics that CEERS and our GTO data can address, I will concentrate my talk on how the MIRI and NIRISS data can be used to study in detail the distinct stellar populations present in galaxies at z=4-7 and beyond, as well as their spatial distribution.
The Transiting Exoplanet Community Early Release Science Program for JWST
Stevenson, Kevin
The James Webb Space Telescope presents the opportunity to transform our understanding of planets and the origins of life by revealing the atmospheric compositions, structures, and dynamics of transiting exoplanets in unprecedented detail. However, the high-precision, time-series observations required for such investigations have unique technical challenges, and our prior experience with HST, Spitzer, and Kepler indicates that there will be a steep learning curve when JWST becomes operational.I will discuss our recently approved ERS program that will accelerate the acquisition and diffusion of technical expertise for transiting exoplanet observations with JWST. This program will also provide a compelling set of representative datasets that will enable immediate scientific breakthroughs. The community will exercise the time-series modes of all four instruments that have been identified as the consensus highest priority, observe the full suite of transiting planet characterization geometries (transits, eclipses, and phase curves), and target planets with host stars that span an illustrative range of brightnesses. I will also discuss plans to engage the community with a two-phase data challenge that culminates with the delivery of planetary spectra, time-series instrument performance reports, and open-source data analysis toolkits.
Star forming galaxies as revealed by gravitational lensing and JWST
Rigby, Jane
Gravitational lensing will uniquely enable JWST to spatially resolve the sub-kiloparsec physical processes within galaxies over most of cosmic time. HST images of lensed galaxies have revealed the ubiquity of <100 parsec star-forming clumps; JWST will dissect each clump spectroscopically, showing the inner process of galaxy assembly. For the first time in the distant universe, JWST will map where stars are forming at high spatial resolution and in an extiction-robust way, using the spectral diagnostics of H-alpha, Pa-alpha, and 3.3um PAH emission. Mid-IR images will reveal the locations of previous generations of stars, showing how star formation has progressed spatially. JWST will measure the physical conditions of nebular gas in these star formation regions -- ionization parameter, pressure,and metallicity -- and how those conditions vary from region to region. JWST will trace the outflows that are launched from these star-forming regions via broad H alpha wings and Na D absorption. The approved DDT-ERS program "TEMPLATES: Targeting Extremely Magnified Panchromatic Lensed Arcs and Their Extended Star formation" will demonstrate these techniques on four of the brightest lensed galaxies known. I will also explore the synergies with rest-frame UV spectra from ground-based telescopes.
AGN demography with JWST - broad-band imaging to the rescue
Messias, Hugo
With available X-ray surveys getting to extreme deep levels with Chandra (~1e-17erg/s/cm2) and probing harder energies with NuSTAR (8-24keV), one may wonder how JWST will contribute to obscured-AGN demography when online. Although deep spectroscopy will be enabled with spectroscopic instrumentation on board JWST (especially with MIRI), such modes will be mostly used for candidate follow-up. This presentation – based on Messias et al. 2012 and 2014, and recent literature developments – aims at showing how deep high-spatial resolution NIRCam and MIRI broad-band imaging can excell in what obscured-AGN demography is concerned with respect to what is currently achieved by X-ray surveys. In the process, some misconceptions undermining the use of this technique will also be addressed. I will show one way to pursue a telescope-time-efficient survey aiming to select AGN up to redshift 2 (and potentially to redshift 6), and what other current science questions such project could address in addition "for free" (i.e., stellar assembly in galaxies or high-redshift source selection).
Establishing Extreme Dynamic Range with JWST: Decoding Smoke Signals in the Glare of a Wolf-Rayet Binary
Lau, Ryan
Dust is a key ingredient in the formation of stars and planets. However, the dominant channels of dust production throughout cosmic time are still unclear. With its unprecedented sensitivity and spatial resolution in the mid-IR, the James Webb Space Telescope (JWST) is the ideal platform to address this issue by investigating the dust abundance, composition, and production rates of various dusty sources. In particular, colliding-wind Wolf-Rayet (WR) binaries are efficient dust producers in the local Universe, and likely existed in the earliest galaxies. Our planned JWST observations of the archetypal colliding-wind binary WR 140 will study the dust composition, abundance, and formation mechanisms. We will utilize two key JWST observing modes with the medium-resolution spectrometer (MRS) on the Mid-Infrared Instrument (MIRI) and the Aperture Masking Interferometry (AMI) mode with the Near Infrared Imager and Slitless Spectrograph (NIRISS).Our planned observations will investigate the dust forming properties WR binaries and establish a benchmark for key observing modes for imaging bright sources with faint extended emission. This will be valuable in various astrophysical contexts including mass-loss from evolved stars, dusty tori around active galactic nuclei, and protoplanetary disks. We are committed to designing and delivering science-enabling products for the JWST community that address technical issues such as bright source artifacts in addition to testing optimal image reconstruction algorithms for observing extended structures with NIRISS/AMI.
Exoplanet Atmosphere Characterization in the framework of the MIRI European Consortium Guaranteed time observations
Lagage, Pierre-Olivier
Thanks to its large collective area and its suite of instruments covering a wide range of wavelengths (0.6-28 microns), the James Webb Space Telescope (JWST) will revolutionize our knowledge about exoplanet atmospheres. The interest in observing exoplanet atmospheres goes well beyond the study of atmospheres very different from those found in the Solar system. Indeed, the molecular composition of giant exoplanet atmospheres can trace the planet's formation and evolution; the atmosphere of rocky exoplanets can host bio-signature gases, …In the talk, I will detail the program of characterization of exoplanet atmospheres to be conducted in the framework of the MIRI European Consortium (EC) Guaranteed Time Observations (GTO). MIRI is the mid InfraRed Instrument of the JWST; it covers the 5-28microns range. One hundred and ten hours, (about ¼ of the MIRI EC GTO used in cycle 1), will be devoted to the characterization of exoplanet atmospheres. All the MIRI observing modes will be used for the program. Imaging observations of five eclipses of the Trappist1 b exoplanet will be combined to detect, for the first time, the emission from an Earth sized exoplanet. The slitless Low Resolution Spectroscopic (LRS) mode will be used to determine the molecular composition of the atmosphere of two transiting exoplanets: WASP107 b, and HAT-P12 b. The good angular resolution of the JWST will make possible the characterization of exoplanets detected by direct imaging. The high contrast imaging mode of MIRI, making use of four quadrant phase mask coronagraphs, will be used to observe the giant planets orbiting HR8799, HD95086 and GJ504. For the exoplanets with not too high a star to planet contrast or with a relatively high angular separation from the host star, such as GU Psc b, observations will be performed in the slit LRS mode or, if bright enough, such as Ross 458 AB b, in the Medium Resolution Spectroscopic (MRS) mode.
Radiative Feedback from Massive Stars as Traced by Multiband Imaging and Spectroscopic Mosaics
Cami, Jan
Massive stars disrupt their natal molecular cloud material by dissociating molecules, ionizing atoms and molecules, and heating the gas and dust. These processes drive the evolution of interstellar matter in our Galaxy and throughout the Universe from the era of vigorous star formation at redshifts of 1-3, to the present day. Much of this interaction occurs in Photo-Dissociation Regions (PDRs) where far-ultraviolet photons of these stars create a largely neutral, but warm region of gas and dust. PDR emission dominates the IR spectra of star-forming galaxies and also provides a unique tool to study in detail the physical and chemical processes that are relevant for inter- and circumstellar media including diffuse clouds, molecular cloud and protoplanetary disk surfaces, globules, planetary nebulae, and starburst galaxies.We will provide template datasets designed to identify key PDR characteristics in the full 1-28 µm JWST spectra in order to guide the preparation of Cycle 2 proposals on star-forming regions in our Galaxy and beyond. We plan to obtain the first spatially resolved, high spectral resolution IR observations of a PDR using NIRCam, NIRSpec and MIRI. We will observe a nearby PDR with well-defined UV illumination in a typical massive star-forming region. This will, for the first time, spatially resolve and perform a tomography of the PDR, revealing individual IR spectral signatures from the key zones and sub-regions within the ionized gas, PDR and molecular cloud. These data will test widely used theoretical models and extend them into the JWST era. We will assist the community through several science-enabling products (maps of spectral features, template spectra, calibration of narrow/broad band filters in gas lines and PAH bands, data-interpretation tools e.g. to infer gas physical conditions or PAH and dust characteristics). This project is supported by a large international team of one hundred scientists collaborators.
Galactic Nuclei Studies with JWST
Luetzgendorf, Nora
Following its launch in 2019, the James Webb Space Telescope (JWST) will be the only facility that is sensitive over the entire near- and mid-infrared spectral range (1 - 28 µm). This wavelength range is extremely rich in spectral diagnostics, both for stellar populations and all components of the interstellar medium (dust as well as neutral, atomic, and ionised gas). Given the diffraction-limited 6.5m aperture of JWST, all of these components can be studied on scales on scales of a few pc in nearby galaxies. In particular, studies with the integral-field spectroscopy modes of the MIRI and NIRSpec instruments promise a wealth of new insights into a number of important issues related to the formation and growth of super-massive black holes, and their effect on the host galaxy. In this talk, I will summarize a number of open issues, and highlight the JWST capabilities that can be used to address them.
AGB stellar populations in resolved galaxies with JWST
Marigo, Paola
Thanks to its spatial resolution and infrared filters, JWST is expected to greatly expand the volume accessible for studies of resolved AGB star populations, hence potentially impacting on the calibration of theoretical models for this critical evolutionary phase. In this talk, we will present the predicted appearance of evolved stars in nearby galaxies using the JWST NIRCam and MIRI filters, investigating, in particular, which filter combinations allow for a better separation of the different types (M and C) of AGB stars, and their expected numbers in SMC-like galaxies located at 4 Mpc.Finally, we will discuss the expectations from The Resolved Stellar Populations Early Release Science Program (ID 1334, PI Dan Weisz), which includes the nearby star-forming dwarf WLM.
Exploring the Solar System with JWST
Hammel, Heidi
JWST’s instruments, along with the telescope’s moving target capabilities, will enable unique and powerful infrared studies of solar system objects. This presentation features highlights of the Solar System guaranteed time observations (GTO), which are also described by Milam et al. 2016 (PASP 128, 959, and references therein). The Solar System GTO program includes observations of Mars, near-Earth objects, asteroids, Jupiter, Saturn as well as its rings and small satellites, Uranus, Neptune, Titan, Europa, Enceladus, several comets, and some transneptunian objects (TNOs). With the exception of the TNO observations, these observations have zero proprietary time, and thus will be immediately available to the community. They will also be available for analysis in the archival research (AR) program in Cycle 1 (the AR program offers support to US investigators for the analysis and interpretation of the Early Release Science programs and these non-proprietary GTO programs to enhance the science return of these datasets). The Solar System GTO program was always planned to enable JWST use by the broad solar system community, so by releasing these data to the community immediately -- as well as having funding opportunities available – we hope to help our colleagues pursue a diverse and comprehensive planetary science program with JWST in future cycles.
Elemental Abundances at Cosmic Time
Kobayashi, Chiaki
Not only metallicity but also elemental abundances can give strong constraints on the formation and evolutionary history of galaxies. Using our cosmological, chemodynamical simulations, we will predict how gas-phase CNO abundances evolve in late-type galaxies and [alpha/Fe] ratios of stellar population in early-type galaxies, both of which will be accessible with JWST. For the former, using the latest yields of asymptotic giant branch stars, we show how the typical star formation history of disc galaxies can be constrained from the time evolution of CNO abundances. For the latter, using our SNIa model that can match a number of observations in the Local Universe, I will discuss when and how star formation should be quenched.
Ice Feature Spectroscopy in Nearby Molecular Cores with JWST NIRCAM
Hodapp, Klaus
This project will study the spatial distribution of continuum extinction and ice absorption features in three nearby molecular cores: B68, a quiescent core, L694-2, a collapsing core, and B335, a star-forming core. All these objects are situated in front of a dense field of background stars so that numerous lines of sight are available for absorption spectroscopy. We are using the slitless grism spectroscopy capabilities of JWST NIRCAM in the 3 - 5 micro-meter range to obtain spectra of all sufficiently bright background stars, and expect roughly 100 usable spectra per core. This will allow maps of the continuum extinction and ice feature absorption depth with unprecedented spatial resolution and will allow us to study the formation and early chemical processing of ice mantles in detail. This paper will also discuss our choice of instrument and observing method, and present details of the implementation of this project with the Astronomer's Proposal Tool (APT).
Lensing-corrected 1.1mm number counts in the ALMA Frontier Fields Survey: A science case for JWST
Muñoz Arancibia, Alejandra
We present galaxy number counts around five strong-lensing galaxy clusters as part of the ALMA Frontier Fields Survey. This aims to characterize the population of faint, dusty star-forming galaxies at high redshift, benefiting from the magnification power of the clusters. Our study combines the analysis of deep (rms ~55-71 uJy/beam) ALMA 1.1mm continuum data over ~23 square arcmin (lens plane) from this survey, with gravitational lensing models produced by different groups. Our estimates for the lensing-corrected number counts consider source detections down to S/N=4.5. Most of these detections lack spectroscopic redshifts, and from those having NIR counterparts, the majority are quite red. Moreover, some detections lack counterparts at other wavelengths, despite the extremely deep Hubble and Spitzer data available for the Frontier Fields clusters. Our ALMA detections thus comprise an interesting population for follow-up observations with JWST, as a robust determination of the missing spectroscopic redshifts will provide better constraints on the source properties, as well as more accurate estimates for the derived number counts.
Observing Programs and Opportunities for Cycle 1
Strolger, Louis-Gregory
I plan to provide an overview of the observing programs for Cycle 1 of JWST. This will include some description of the planned Guaranteed Time Observations, provided in return for contributions to the development of key components of the observatory. I will also cover the planned Director’s Discretionary Early Release Science observations, an initiative to accelerate access to data and science products and realize JWST’s full science potential. Lastly, I will discuss the opportunities and timeline for General Observer and Archival programs in the cycle.
Establishing Extreme Dynamic Range with JWST: Decoding Smoke Signals in the Glare of a Wolf-Rayet Binary
Madura, Tom
Dust is a key ingredient in the formation of stars and planets. However, the dominant channels of dust production throughout cosmic time are still unclear. With its unprecedented sensitivity and spatial resolution in the mid-IR, the James Webb Space Telescope (JWST) is the ideal platform to address this issue by investigating the dust abundance, composition, and production rates of various dusty sources. In particular, colliding-wind Wolf-Rayet (WR) binaries are efficient dust producers in the local Universe, and likely existed in the earliest galaxies. Our planned JWST observations of the archetypal colliding-wind binary WR 140 will study the dust composition, abundance, and formation mechanisms. We will utilize two key JWST observing modes with the medium-resolution spectrometer (MRS) on the Mid-Infrared Instrument (MIRI) and the Aperture Masking Interferometry (AMI) mode with the Near Infrared Imager and Slitless Spectrograph (NIRISS).
Atmospheric Characterization of Exoplanets with JWST
Doyon, Rene
Thanks to new ground- and spaced-based facilities, the nearest exoplanets will soon be unveiled, including bright, transiting systems amenable for detailed atmospheric studies, from hot Jupiters to temperate rocky worlds potentially harbouring life. JWST instruments will have unique capabilities to probe the atmosphere of exoplanets with unprecedented sensitivity and wavelength coverage. JWST will mark a new era of exoplanet characterization, a major stepping-stone towards the detection of biological activity beyond the Solar system. This presentation will highlight JWST’s unique capabilities for exoplanet studies and present some of its science programs dedicated to atmospheric characterization of exoplanets with a focus on the NIRISS GTO program. I will also discuss the rationale for a major legacy/treasury program of transit/eclipse spectroscopy with JWST beyond Cycle 1.