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Poster Abstracts

Characterizing the Physical Conditions of Local Luminous Infrared Galaxies: The First Step to Understanding Their More Distant Cousins
Dr.  Almudena Alonso-Herrero (Instituto de Estructura de la Materia, CSIC)
Luminous Infrared Galaxies, LIRGs (LIR=10^11-10^12Lsun), provide insights to star formation and nuclear activity under extreme conditions. Moreover, although locally they only contribute to a small fraction of the infrared background, they are the major contributors to the obscured star formation rate (SFR) density at redshift z=1, when the universe was half of its present age. We are carrying out a project to study the properties of a complete volume-limited sample of LIRGs. The typical distances (d=35-75Mpc) of these LIRGs allow us to probe regions on scales of tens-hundreds of parsecs. The observations include high-spatial resolution HST imaging, ground-based optical and near-infrared integral field spectroscopy, and mid-infrared imaging and spectroscopy (Gemini/T-ReCS and Spitzer). We will present recent results on the properties (ages, extinctions, SFRs, stellar and dynamical masses) of the nuclei, star clusters, and the youngest star forming regions as well as the excitation conditions and kinematics of the nuclear and extra-nuclear regions of nearby LIRGs. The final goal of this project is to characterize in local LIRGs the physical conditions giving rise to their high infrared luminosities, as a stepping stone to understanding their more distant counterparts. JWST will allow us to probe similar physical sizes (tens to hundreds of parsecs) for LIRGs at intermediate redshifts.
Current and Future High-Contrast Thermal Infrared Imaging Surveys for Giant Planets
Dr.  Daniel Apai (Steward Observatory / NASA Astrobiology Institute)
I present an overview of the current status and the future prospectives of high-contrast thermal infrared imaging of exoplanets. High-contrast imaging at wavelengths longer than 3-5 micron benefits from high image quality and efficient adaptive optics correction. In addition, on current low thermal background ground-based telescopes these wavelengths offer the sensitivity to directly image and study planets as old as a 2-4 Gyr. As such old systems can now be studied, the immediate vicinity of the Solar neighborhood becomes accessible. Current instrumentation can already probe the giant planet population in these systems on physical scales of 4-6 AU. As an example, I will present results from two ongoing L-band adaptive optics surveys on the MMT and on the VLT that constrain the radial extent of the giant planet population and suggest a cut-off at radii smaller than 15 AU. Finally, I will discuss the future prospectives for high-constrast imaging on large ground-based telescopes in the next decade and place it in the context of the James Webb Space Telescope.
Optical Interferometry in the Next Decade
Dr.  Eric Bakker (New Mexico Tech/Magdalena Ridge Observatory)
Ground-based optical/infrared long-baseline interferometry has come of age in the U.S. where several existing or planned facilities have produced remarkable scientific results demonstrating the power of the technique within a broad range of scientific applications. This paper presents brief overviews of the following facilities: the Palomar Testbed Interferometer (PTI) on Mt. Palomar, CA; the Navy Prototype Optical Interferometer (NPOI) located on Anderson Mesa near Flagstaff, AZ; the Keck Interferometer (KI) on Mauna Kea, HI; and the CHARA Array on Mt. Wilson, CA. Also described is the Magdalena Ridge Observatory Interferometer (MROI) to be built at the highest elevation of the Magdalena Mountains of New Mexico. Example scientific highlights to date include: The first measurement of stellar rotational oblateness (Altair), the detection of Cepheid pulsations, and ultra-precise astrometry of binaries with PTI; the first six-telescope images (the triple system eta Virginis) and constraints on disk parameters of Be stars with NPOI; resolving the nucleus of NGC 4151 and probing the inner disk regions of YSOs with KI; and, the first direct detection of gravity darkening in single stars (Regulus), calibration of the Baade-Wesselink method for Cepheids, and the first direct measurement of the diameter of an exoplanet (the transit system HD 189733) using the CHARA Array. While the great majority of results to date have focused on stellar astrophysics, the MROI strives to have sensitivity sufficient to access a number of AGN. Research with these independently operated facilities is sponsored by the California Institute of Technology and the Jet Propulsion Laboratory for PTI; the U.S. Naval Observatory and the Naval Research Laboratory for NPOI; the National Aeronautics and Space Administration for KI; and, the National Science Foundation and Georgia State University for the CHARA Array. Funding for MROI is administered through the Office of Naval Research.
Cosmology with an Optical Interferometer
Dr.  Eric Bakker (New Mexico Tech/Magdalena Ridge Observatory)
AGN broad-line emission regions (BELRs) have measureable sizes in physical units using the 'Reverberation Mapping' technique: AGN continuum radiation is highly variable and, as this radiation excites the BELs (typically at distances of 0.01-1 pc from the central continuum source), the time delay between the variations in the continuum and those in the BEL gives the distance of the BELR from the continuum. If the angular size of the BELR can also be measured, via optical interferometry, then these two observables provide a direct geometrical measure of the distance to the AGN, and a measure for the Hubble constant. Doing this exercise for AGNs at different redshifts will can map out the metric, in principle to z>6 (Elvis & Karovska, 2002). Near-IR spectroscopy shows a number of candidate BELs in the Paschen and Brackett series that have sufficient flux (Landt et al., 2007) to attempt this measurement using interferometers with capabilities comparable to the Magdalena Ridge Observatory in the next few years (Creech-Eakman et al. 2006). The observational capabilities to observe structures in the milliarcseconds range in the visible and infrared are only provided by optical interferometers with baselines of several hundred meters. However the current generation optical interferometer have a limiting magnitude of only K'= 10.3 (Keck) and N=4 and K=7 (VLT UTs). Other interferometers in operations (CHARA, NPOI, ISI, and PTI) have lower limiting magnitudes and no access to extra-galactic objects. With these limiting magnitudes the amount of accessible objects if a few (6 observed with the VLTI, 1 with Keck). Even in the era of JWST, ALMA, and SKA, spatial resolution of less than 1 milliarcseconds will only be available through optical interferometry, although for only the brighter objects. The Magdalena Ridge Observatory Interferometer is under construction and is designed for a limiting magnitude of H=14. In the K-band (2.2 micron), the longest baseline of 340m will provide a nominal resolution of about 1 milliarcseconds. The gap between the required resolution of < 0.1 milliarcseconds to measure the BELR and available resolution of 1 milliarcseconds can be covered by advanced modeling and using visibility data beyond the first null. Preliminary studies are underway to investigate the feasibility to conduct an extensive survey of AGNs with the MRO interferometer in an attempt to determine an absolute distance scale to the AGNs, the Hubble and the cosmological constant.
Stratospheric Observatory for Infrared Astronomy (SOFIA)
Prof.  Eric Becklin (USRA-SOFIA)
The joint U.S. and German SOFIA project to develop and operate a 2.5 meter infrared airborne telescope in a Boeing 747-SP is now in it final stages of development. Flying in the stratosphere, SOFIA allows observations throughtout the infrared and submillimeter region, with an average transmission of greater than 80%. SOFIA has a wide instrument complement including broadband imagers, modrate resolution spectrographs capable of resolving broad features due to dust and large molecules, and high resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km/s resolution. These and future instruments will enable SOFIA to make unique contributions to a broad array of science topics. First science flights will begin in 2009, and the observatory is expected to operate for more than 20 years. The sensitivity, characteristics, science instrument complement, examples of first light science and complimentary observations to JWST are discussed.
The EXIST-JWST Synergy
Prof.  Joshua Bloom (UC Berkeley)
The Energetic X-ray Imaging Survey Telescope (EXIST) is a proposed Black Hole Finder (Beyond Einstein) mission that would fly contemporaneously with JWST. As a follow-up agent for EXIST-discovered transients, JWST is uniquely positioned to impact major science objectives of the EXIST mission. In particular, we highlight the JWST-EXIST synergy for observing very high-redshift (z > 10) gamma-ray bursts and black hole tidal disruption events out to moderate redshifts.
Supernovae Remnants in the Mid-infrared
Dr.  Patrice Bouchet (Service d'Astrophysique, DAPNIA/DSM, CEA Saclay)
Abstract not available at this time.
Mapping Reionization: The Science and Technology of Redshifted 21 cm Tomography with Upcoming Low-Frequency Radio Arrays
Dr.  Judd Bowman (Caltech)
Features in the diffuse radio background below 200 MHz due to the hyperfine 21 cm transition line of neutral hydrogen in the high-redshift IGM should provide an extraordinary probe of reionization. Local variations in the density, temperature, and ionization fraction of the IGM are predicted to be revealed as spatial fluctuations in the intensity of the background. Characterizing the spatial power spectrum of the fluctuations and eventually mapping the exact patterns (as functions of both angle and frequency) should yield information on the processes responsible for reionization and the history of the IGM, and complement observations with the JWST and other concurrent facilities. Three new low-frequency radio telescope arrays with the potential to detect fluctuations in the redshifted 21 cm background during the reionization epoch are currently under construction: the Mileura Widefield Array (MWA), the Low Frequency Array (LOFAR), and the 21 cm Array (21CMA). These projects are developing the techniques needed to measure the redshifted 21 background and should demonstrate the feasibility of the measurements by 2010. In a time frame concurrent with that of the JWST, it is anticipated that one or more of these initial efforts will have evolved into a facility capable of mapping the fluctuations in the redshifted 21 cm background with significant detail. In particular, the MWA is designed specifically to detect the power spectrum of fluctuations in the 21 cm emission between redshifts 6 and 12. When completed, the array will have a collecting area similar to the VLA (about 1% of the SKA), but will consist of 500 antenna tiles scattered over a region only 1.5 km in diameter. Simulations indicate that a foreseeable increase in the collecting area by a factor of 10 would be sufficient to significantly constrain the reionization history. Among the challenges faced by these experiments, the separation of Galactic and extragalactic foreground contaminants from the desired signal is expected to be particularly difficult. As with CMB observations, the astrophysical foregrounds in redshifted 21 cm measurements are approximately five orders of magnitude brighter than the (~10 mK) signal and can only be isolated due to their spectral properties.
SPICA and BLISS: A Large Cold Observatory enables Sensitive Far-IR Spectroscopy in the Next Decade
Dr.  Charles (Matt) Bradford (JPL / Caltech)
We present an overview of SPICA and highlight potential US technical contributions to the mission. SPICA is a JAXA-led mission to L2 featuring a 3.5-meter telescope actively cooled to below 5K, and is envisioned for launch in 2017. With the cold aperture, SPICA offers the potential for mid-IR to submillimeter observations limited only by the zodiacal dust emission and other natural backgrounds. SPICA can thus enable sensitivities comparable to those of JWST but extended to the longer wavelengths, a dramatic improvement relative to Herschel and SOFIA. SPICA has a strong following in Europe, and telescope and instrument contributions are under consideration by ESA and its member states. The very low-background platform is especially compelling for moderate-resolution spectroscopy. Our group at JPL is developing technologies and studying concepts for BLISS, a background-limited infrared-submillimeter spectrometer for SPICA. BLISS / SPICA can cover the 40-600 microns range using bolometers with sensitivities close to the photon background limit. The resulting line sensitivities approach 10^-20 W m^-2 in modest integrations. This new capability will enable the survey spectroscopy of the redshift 0.5 to 5 galaxies which produce the cosmic far-IR background. The far-IR fine-structure and molecular transitions which BLISS / SPICA will measure are immune to dust extinction, and will unambiguously reveal these galaxies redshifts, stellar and AGN content, gas properties, and metallicities; in aggregate the history of the population. BLISS for SPICA also provides a demonstration platform for key technologies in preparation for even more capable US-led far-IR observatories such as SAFIR in the 2020 decade.
Mapping the Reionization Epoch with the Ly-alpha emission from Quasar Ionization Fronts
Sebastiano Cantalupo (ETH Zurich)
We present a new method to directly map the HI distribution during the reionization epoch and to constrain the emission properties of the high-z quasars (QSOs). As a tracer of HI, we propose to use the Ly-alpha radiation produced by HI collisional excitations within the QSO ionization fronts (I-fronts) that expand in the Intergalactic Medium (IGM) before reionization is complete. Combining two radiative transfer models (one for the QSO ionizing radiation and one for the Ly-alpha photons), we estimate the expected Ly-alpha spectral shape and surface brightness (SB) for a large number of configurations where we varied both the properties of the ionizing QSO and of the surrounding medium. We find that the expected signal is observable as a single emission line with a characteristic width of 100-200 km/s. The expected SB produced at redshift z~6.5 within a fully neutral region (at mean density) by a typical QSO I-front is of the order of $10^{-20} erg s^{-1} cm^{-2} arcsec^{-2}$ and decreases proportionally to $(1+z)^2$ for a given QSO age. QSOs with harder spectra may produce a significantly brighter emission at early phases. The signal may cover up to a few hundred square arcmin on the sky and should be already detectable with current facilities by means of moderate/high resolution spectroscopy. With JWST we will be able to map the HI distribution on arcmin scales in a broad redshift range. The detection of this Ly-alpha emission can shed new light on the reionization history, the age and the emission properties of the highest-redshift QSOs.
A Phase Apodization Coronagraph for the JWST
Dr.  Johanan Codona (Steward Observatory, University of Arizona)
We propose a single pupil optic for the JWST to provide a coronagraphic capability from 2 to 10 lambda/D around a target star. The optic uses Phase Apodization Coronagraphy (PAC), a new technique for suppressing the diffraction pattern of a telescope. PAC is straightforward, robust, and has been demonstrated on-sky at 5 microns with the 6.5 m MMTO telescope. The PAC optic is a diamond-turned element that is placed into a pupil filter wheel and rotated in when a coronagraphic capability is required. PAC doesn't require careful telescope pointing above that for direct imaging, since there is no focal plane mask or Lyot stop. Furthermore, avoiding the use of a Lyot stop allows the angular resolution of the telescope to be largely preserved. The method is capable of suppressing the halo to more than 4 - 5 decades below the peak of the star by the first Airy ring, something that is well beyond the reach of a Lyot-style coronagraph.
Defining the Benchmark Local Galaxy Luminosity Function Using 2MASS
Prof.  Nick Devereux (Embry-Riddle Aeronautical University)
Nearby galaxies manifest in a variety of shapes and sizes, forming the basis of a morphological classification scheme whereby galaxies are segregated into ellipticals, lenticulars and spirals. However, recent observations with NASA�s Hubble and Spitzer Space Telescopes have shown that distant galaxies at z ~ 2 are completely unrecognizable. Understanding the metamorphosis of galaxy morphology is central to understanding how galaxies formed, and how they changed over time into the objects recognized in the present universe. Quantifying the space density of galaxies as a function of luminosity is a key diagnostic in understanding the evolution of galaxy morphology. The local galaxy luminosity function, as defined by nearby galaxies, is the benchmark against which luminosity functions for more distant galaxies are compared. The primary objective of this poster is to present the first benchmark near infrared luminosity functions for nearby galaxies, segregated by morphological type. The results set the stage for future observations using NASA�s James Webb Space Telescope.
The JWST Tunable Filter Imager (TFI)
Dr.  Rene Doyon (Universite de Montreal)
The Fine Guidance Sensor (FGS) of the James Webb Space Telescope (JWST) features a tunable filter imager (TFI) module covering the wavelength range from 1.5 to 5.0 m at a resolving power of ~100 over a field of view of 2.2�x2.2�. TFI also features a set of 4 occulting spots for coronagraphy. This paper will review the current design and development status of TFI and will highlight its key science programs, from the detection of first light, high-redshift Ly emitters to the detection and characterization of exoplanets.
Con-X
Dr.  Michael Garcia (Smithsonian Astrophysical Observatory)
The 2000-2010 Decadal Survey ranks Con-X next in priority after JWST among large space observatories. Con-X will operate concurrently with JWST in a manner similar to the current synergy between Chandra and Hubble and Spitzer. Four science topics which drive the configuration of the mission include 1) testing GR via tracking the orbits of material in the innermost edges of accretion disks around black holes, 2) tracing cosmological structure (e.g., dark energy) via studies of clusters of galaxies, 3) finding the missing baryons likely present in the warm-hot intergalactic medium and 4) determining the equation of state of ultra-dense matter in neutron stars. These topics will be addressed via high throughput and high dispersion x-ray spectroscopy. As a flagship mission within NASA's Beyond Einstein program, Con-X will naturally cover a wide range of astrophysics ranging from solar system to cosmological studies and extending well beyond these four driving science topics. Observations will be open to the entire astronomical community and selected via a peer-view process. The baseline configuration includes four large X-ray telescopes feeding x-ray calorimeters and a diffraction grating assembly, as well as two smaller high energy telescopes, all housed in a single spacecraft. This poster will describe the technical configuration and capabilities of the observatory and some of the science topics in which Con-X will make breakthrough observations.
Progress by the JWST Science Working Group
Jonathan Gardner (NASA's GSFC)
The JWST Science Working Group recently published a comprehensive, top-level review of JWST science in the journal Space Science Reviews (Gardner et al. 2006, SSR, 123, 485). That review paper gives details of the 4 JWST science themes, and describes the design of the observatory and ground system. Since publication, the SWG, working with members of the astronomical community, has continued to develop the science case for JWST, giving more details in a series of white papers. The white paper topics include first light, galaxy surveys, AGN, supernovae, stellar populations, and exoplanets. The white papers are in various stages of completion. In this poster, I will review recent progress.
Simulating MIRI Medium Resolution Spectrometer observations of Young Stellar Objects
Dr.  Alistair Glasse (UKATC)
We present model spectral images of distant YSOs, as they would appear when observed by the JWST MIRI instrument's Medium Resolution Spectrometer (MIRI-MRS). The YSO spectra include both broad silicate dust absorption features and narrow molecular lines, to illustrate the capabilities of the MRS and to highlight some of the data analysis issues associated with this type of integral field spectrometer.
An new infrared observatory in Southern Utah
Prof.  Paolo Gondolo (University of Utah)
As part of an initiative to establish astronomy at the University of Utah, we are setting up a new optical/infrared observatory in Southern Utah. The first instrument will be a 36-in robotic telescope equipped with an infrared spectrograph and camera. The first science goals will include follow-ups of extrasolar planets and monitoring of active galactic nuclei. The observatory will be situated at an elevation of about 11,000 ft (3300 m), and will take advantage of the dry climate of Southern Utah. The observatory will also be part of a growing outreach program at the University.
Understanding the Aromatic (PAH) Freatures with JWST
Karl Gordon (STScI)
The imaging and spectroscopic capabilities of JWST will allow advances in our understanding of the excitation and modification/destruction of the aromatic features. The aromatic features (also called the PAH features) are emission features between 3.3 to 18 microns which are almost always seen when dust is found in emission. The combination of the highly sensitive and excellent spatial resolution imaging of NIRCam and MIRI can be combined to determine the wavelength of excitation of the aromatic features including variations between aromatic features. This has already been done for Extended Red Emission, which is an optical emission feature of dust, using HST ACS & NICMOS imaging of narrow filaments in the reflection nebula NGC 7023 (Witt et al. 2005). The very sensitive NIRSpec and MIRI spectroscopy in the mid-infrared can be used to probe the modification/destruction mechanisms of the aromatics seen with Spitzer/IRS (Engelbracht et al. 2007; Gordon et al. 2007) that depend on radiation field hardness/metallicity. These high S/N measurements of the aromatic feature ratios will be used to probe ionization and size selective modification/destruction mechanisms of the aromatic features.
Surface Brightness Profiles of Composite Images of Compact Galaxies at z~4-6 in the HUDF
Nimish Hathi (Arizona State University)
The Hubble Ultra Deep Field (HUDF) contains a significant number of B, V and i'-band dropout objects, many of which were recently confirmed to be young star-forming galaxies at z~4-6. These galaxies are too faint individually to accurately measure their radial surface brightness profiles. Their average light profiles are potentially of great interest, since they may contain clues to the time since the onset of significant galaxy assembly. We separately co-add V, i' and z'-band HUDF images of sets of z~4,5 and 6 objects, pre-selected to have nearly identical compact sizes and the roundest shapes. From these stacked images, we are able to study the averaged radial structure of these objects at much higher signal-to-noise ratio than possible for an individual faint object. Here we explore the reliability and usefulness of a stacking technique of compact objects at z~4-6 in the HUDF. Our results are: (1) image stacking provides reliable and reproducible average surface brightness profiles; (2) the shape of the average surface brightness profiles show that even the faintest z~4-6 objects are resolved; and (3) if late-type galaxies dominate the population of galaxies at z~4-6, as previous HST studies have shown, then limits to dynamical age estimates for these galaxies from their profile shapes are comparable with the SED ages obtained from the broadband colors. We also present accurate measurements of the sky-background in the HUDF and its associated 1-sigma uncertainties.
Constellation-X and JWST: Concurrent X-ray and Infrared Great Observatories
Dr.  Ann Hornschemeier (NASA GSFC)
Great synergy has been enjoyed between NASAs current Great Observatories and we expect that this will continue in the next decade with the concurrent operation of both Constellation-X and JWST. The great increase in sensitivity offered by these two observatories, working in unison, will be required for a number of key science investigations, several of which we describe in this poster. For instance, although >80% of the cosmic X-ray background is resolved at 2-8 keV in the deepest Chandra surveys, the peak of the cosmic X-ray background remains largely unexplained (at energies of 8-40 keV). There may be a significant population of obscured (perhaps Compton-thick) AGN that produce this part of the extragalactic background radiation, and Constellation-Xs large collecting area and spectroscopic capabilities over the 1-40 keV bandpass will allow determination of the nature of the obscuring material. This obscured nuclear emission is expected to be re-emitted at longer wavelengths and hence mid-infrared (MIR) observations can be crucial to reveal obscured AGN emission. However, current photometric observations in the infrared are limited by contamination from star formation, requiring moderate-to-high resolution IR spectroscopy (provided by JWST). In addition, Con-X and JWST will make great advances in unraveling the nature of the highest redshift AGN (4 < z < 8; and possibly z>8) down to Seyfert luminosities and will probe the formation and evolution of galaxy groups and clusters. Studies of the largest clusters of galaxies (i.e., the largest gravitationally-bound structures in the Universe), allow constraint of important cosmological parameters such as G(z) and w. This poster describes these science areas and briefly touches upon the role of the various Con-X and JWST instruments in these science investigations.
The Constellation-X Spacecraft: One Spacecraft Launching on an Atlas V
Dr.  Ann Hornschemeier (NASA GSFC)
This poster shows the current reference design for the Constellation-X spacecraft, which will be launched on a single Atlas V launch vehicle to an L2 orbit.
The Constellation-X X-ray Microcalorimeter Spectrometer
Dr.  Ann Hornschemeier (NASA GSFC)
The X-ray Microcalorimeter Spectrometer (XMS) on Constellation-X will provide imaging and high-resolution spectroscopy in the 0.6-10 keV band. The XMS provides spatially-resolved spectra over a field of view of approximately 5 x 5 arcminutes and will be ideal for studying extended sources such as clusters of galaxies and supernova remnants. The XMS uses an X-ray microcalorimeter to sense individual X-ray photons as heat, and determine their energy with high precision. Thermodynamic limits determine the spectral resolution and drive the need for operation at a temperature below ~0.1 K. This poster describes the instrument, including the cryogen-free cryocooler that is based on technology being developed for the JWST MIRI instrument.
The Fine Guidance Sensor for the JWST
Dr.  John Hutchings (HIA)
Details are presented of the design and performance of the Guider cameras for the JWST. The poster will show limiting centroiding accuracy, operational options, and systematic effects in stepping across the detector pixel arrays. We also discuss the numbers of guide stars available at the galactic poles, and the effects of focus change and double stars.
Transient Spectroscopy of Planets: From Spitzer to JWST
Dr.  Oliver Krause (Max-Planck-Institut for Astronomy)
2007 was a brakethrough year in the field of planetary sciences as, for the first time, infrared spectra could be obtained of exo-solar giant planets with Spitzer. These results mark the steps towards comparative studies of the chemistry and physical conditions of planetary atmospheres outside of the solar system. We will discuss the new Spitzer results and their implications and provide a view into the future towards JWST when, with its superior performance, the field of transient spectroscopy of planets is expected to take flight.
The earliest phases of high-mass star formation: Opportunities with JWST
Dr.  Oliver Krause (Max-Planck-Institut for Astronomy)
We discuss the scientific potential of JWST, in particular the MIRI instrument, for the study of massive cores and protostars.
Universe's Universal Molecules
Dr.  Fred Lahuis (SRON Netherlands Institute for Space Research/Leiden Observatory)
After the ISO mission water was proclaimed the universal molecule for being observed in a wide variety of objects. In the last few years it has been shown that three more molecules may with equal merit be called universal. Acetylene, hydrogen cyanide and carbon dioxide have provided very strong diagnostics in the study of warm gas in extremely diverse sources. Acetylene and hydrogen cyanide both trace regions of warm dense gas and are important molecules in the hydrocarbon and nitrogen chemistries. In this poster we give examples of observations of acetylene, hydrogen cyanide and carbon dioxide with ISO and Spitzer in our own Galaxy and ultraluminous infrared galaxy nuclei. In our own Galaxy we present observations of the molecules in the inner planet forming zone of the circumstellar disk around a young low-mass star and the inner envelopes around massive young stars. In the galaxy nuclei the observed molecules are believed to trace a form of 'trapped' star formation in the extremely dense nuclear medium. James Webb MIRI observations of these molecules will be very important. The higher resolving power of MIRI compared to Spitzer-IRS will allow detections at much lower column densities while the higher spatial resolution will provide better information about the distribution of the warm molecular gas.
Project Lyman -- SMEX mission defining LyA as a LyC proxy for JWST reionization investigations
Dr.  Stephan McCandliss (Johns Hopkins University)
A key goal for the James Webb Space Telescope (JWST) is to identify the sources responsible for initiating and completing the epoch of reionization, which followed the collapse and formation of the first luminous structures. The first structures emit ionizing radiation in the Lyman continuum (LyC) spectral region shortward of 912 Angstroms. A fraction of the LyC escapes (f^c_e) into the surrounding intergalactic medium (IGM) and creates the metagalactic ionizing background (MIB -- an important source of positive radiative feedback that can further enhance the collapse of structure, Ciardi 2007). A fraction of the LyC is absorbed by neutral hydrogen in the surrounding interstellar medium (ISM) and reemitted in a recombination line cascade. Candidates for the sources of reionization include active galactic nuclei (AGN) and star-forming dwarf galaxies (DG). AGN have high f^c_e, but near z ~ 6 they are low in number. DG have low f^c_e, but are numerous around z ~ 6 and are favored over AGN as the dominant reionization source, if their f^c_e is high enough (Windhorst et al. 2006). Direct detection of escaping LyC radiation at high redshift is frustrated by intervening Lyman limit systems (Shapley et al. 2006), leaving the Lyman alpha (LyA) recombination line as the primary diagnostic available to JWST for probing the reionization z >~ 6 (Stiavelli et al. 2004). However, LyA is only an indirect indicator of LyC radiation, because the intensity of LyA is proportional to the amount of LyC that does NOT escape. Furthermore, the escape of LyA (f^a_e) is complicated by resonance scattering in a multiphased ISM, which is strongly influenced by the local dust geometry and velocity fields (Neufeld 1991, Hansen and Oh 2006). LyA emission line measurements can confirm that LyC radiation is emitted within a structure. However, a quantitative characterization of the relationship between LyA and LyC escape remains elusive, in large part because of the difficulty of directly detecting LyC from star-forming galaxies at any epoch (Leitherer et al. 1995, Hurwitz et al. 1997, Shull et al. 1999, Heckman et al. 2001, Steidel et al. 2003, Bergvall et al. 2006, Shapley 2006, Grimes et al. 2007). An observational effort to establish a proxy relationship between LyA and LyC is required to enable quantitative investigations into the reionzation epoch by JWST. Here we outline a SMEX mission concept called Project Lyman, which is focused on quantifying this relationship in nearby, galactic environments. Project Lyman seeks to directly detect the relative contributions of star-forming galaxies and quasars to the MIB at z < 0.9 and to make LyA measurements at z < 0.4. By observing a variety of spatially resolved galaxies we will gauge the effects of viewing angle with respect to local geometry, dust, metallicity and velocity fields on the escape of LyA and LyC and achieve a clear understanding of these properties in the angle averaged view afforded by high redshift observations. Guided by number counts of GALEX far-UV sources (Xu et al. 2005), we present estimates for the number of observable objects to a given background limit (McCandliss 2006) and from this derive the sensitivity requirements necessary for pushing the detection limits on f^c_e < 0.01. The design of a dual order integral field spectro/telescope (McCandliss et al. 2004) with a (0.5 deg)^2 FOV, featuring a Goddard Space Flight Center microshutter array, a UCB crossed delay-line microchannel plate detector, and a JHU optical design, is presented. We call this instrument FORTIS, short for Far-uv Off Rowland-circle Telescope for Imaging and Spectroscopy. This work supported by NASA suborbital program research grant to JHU NNG04WC03G.
Spitzer Survey of the Large Magellanic Cloud: Surveying the Agents of a Galaxy's Evolution (SAGE); Initial results and Potential JWST followup
Dr.  Margaret Meixner (Space Telescope Science Institute)
We are performing a uniform and unbiased imaging survey of the Large Magellanic Cloud (LMC, ~77), using the IRAC (3.6, 4.5, 5.8 and 8 m) and MIPS (24, 70, and 160 m) instruments on board the Spitzer Space Telescope (Spitzer) in order to survey the agents of a galaxy�s evolution (SAGE), through the interaction between the interstellar medium (ISM) and stars in the LMC. Three key science goals determined the coverage and depth of the survey. The detection of diffuse ISM with column densities >1.2x1021 H cm-2 permits detailed studies of dust processes in the ISM. SAGE�s point source sensitivity enables a complete census of newly formed stars with masses >3 M that will determine the current star formation rate in the LMC. SAGE�s detection of evolved stars with mass loss rates >1x10-8 M yr-1 will quantify the rate at which evolved stars inject mass into the ISM of the LMC. The observing strategy includes two epochs in 2005, separated by three months, that both mitigate instrumental artifacts and constrain source variability. The SAGE data are non-proprietary and point source lists will be released to the community in support of Spitzer proposal cycles 4 and 5. The SAGE epoch 1 point source catalog has ~4x106 sources and a measured point source sensitivity for the epoch 1 data is consistent with expectations for the survey. This poster provides an overview of the SAGE legacy project including initial results in the three key science areas. Followup on SAGE results with the James Webb Space Telescope are discussed. The SAGE Project is supported by NASA/Spitzer grant 1275598 and NASA NAG5-12595.
Kuiper Belt Binaries with JWST
Dr.  Keith Noll (Space Telescope Science Institute)
One of the surprising features of the Kuiper Belt, the torus of small bodies that orbits the Sun beyond Neptune, is that a large fraction of objects are binary. Over 50 such binary systems have been discovered since 2001, most with HST. These objects will be among the most productive targets in the Kuiper Belt for JWST. Binaries offer several advantages that can be exploited by the combination of sensitivity and angular resolution offered by JWST. Because masses and densities are known or constrained for these objects, additional physical observations made by JWST will be enhanced. Near infrared spectra of individual components of binaries, data that JWST will be uniquely capable of providing, will provide compositional information for objects that are presumed to be coeval. Differences in object spectra, if any are found, would point to divergent evolutionary processes, presumably impacts. Statistical studies of many objects can be expected to reveal patterns that may distinguish between possible histories. I will review the current state of studies of Kuiper Belt binaries as a foreshadowing of the richly diverse Kuiper Belt science that will be enabled by JWST.
Lights in the dark ages: Gamma-ray bursts in the early Universe
Dr.  Paul O'Brien (University of Leicester)
Long duration Gamma-ray bursts are the most powerful sources of light in the Universe, detectable out to redshifts of around 20. GRBs provide a unique probe of the early Universe as they are predicted to exist at epochs before those of the growth of super-massive black holes or large galaxies. As GRBs are associated with massive stars, they can be used to locate sites of early star formation. Initially GRBs provide a bright background light source against which to observe the growth of metals via absorption line spectroscopy and allow a study of the era of re-ionisation. Unlike QSOs, GRBs fade away to provide a clear view of the host galaxy. Future, more powerful observing facilities such as JWST can be used to study the morphology and star formation history of the host galaxies of high redshift GRBs identified through localisations from the Swift satellite and future missions. A gamma-ray selected galaxy sample will provide an unbiased look at the star formation history of the Universe.
Accretion in protoplanetary disks: sticking chondrules together.
Mr.  Chris Ormel (Kapteyn Astronomical Institute)
Chondrules, mm-sized igneous particles, are one of the oldest fossils of our solar system. They are a conspicuous component of chondritic meteorites, but, in most cases, not the only one. Micron-sized dust grains permeate chondrites in the form of a densely-packed rim around chondrules and more loose matrix material. How did this dust mix with the chondrules? Moreover, how did these sub-mm grains accrete together into planetesimal sized objects in the nebula? Here, we present an accretion scenario in which the dust enables chondrules to stick together. In it, chondrules accrete a porous rim, which will be compacted upon collisions with other chondrules, dissipating the collisional energy and allowing the chondrules to stick. We investigate how much growth can be achieved through this mechanism by running a parameter study, varying the many (and unknown) parameters characterizing the protoplanetary disk. It is found that, under the most favorable conditions, considerable growth can take place, although even then the planetesimal size is not reached. We discuss implications for the internal structure of the primitive meteorites, especially on the properties of chondrule dust rims.
The evolution of gas in protoplanetary disks
Dr.  Ilaria Pascucci (Steward Observatory, The University of Arizona)
The initial mass and lifetime of gas in protoplanetary disks determine the final mass and formation time of giant planets. In addition, residual gas in disks of several Myr influences the outcome of terrestrial planet formation. I will review the observations constraining the evolution and dissipation of gas in protoplanetary disks and discuss their implications on theories of giant and terrestrial planet formation. I will summarize the outstanding issues and discuss how future facilities will help to solve them.
Planetary Debris Disks: Spitzer to JWST
Prof.  George Rieke (University of Arizona)
Debris disks reveal the evolution of the middle and outer regions of planetary systems - from one to hundreds of AU. They complement studies of the inner regions through Doppler recoil measurements and transits. Spitzer (building on IRAS and ISO) has found more than a hundred debris disks within 50 pc and hundreds more in distant clusters (important to characterize very young systems). The observations establish a general similarity between the behavior of these other planetary systems and the Solar System: 1.) the overall time scale for the central 10-20 AU region in disks fading is a few hundred Myr, parallel to the time up to the Late Heavy Bombardment in the Solar System; 2.) the outer parts of disks appear to be roughly stable for many Gyr, as is also the case for the Kuiper Belt; and 3.) there are occasional large collisonal events that substantially enhance the amount of debris around a star, a situation that must have held for the Solar System when the moon was formed. JWST will build on this work, particularly by obtaining detailed images and spectra of the nearby systems - it should be capable of resolving all the systems within 50 pc. The resulting images will enable us to remove degeneracies in the current disk models and to examine directly the possible influence of massive planets on debris disk structure.
NIRCam: the Near-Infrared Imager and Wavefront Sensor for JWST
Prof.  Marcia Rieke (Steward Observatory)
NIRCam for JWST will have unprecedented sensitivity in the near-infrared. How this sensitivity is achieved, and the key design features of NIRCam will be presented.
SPACE - The SPectroscopic All-sky Cosmic Explorer
Dr.  Massimo Robberto (STScI)
The SPectroscopic All-sky Cosmic Explorer (SPACE) is a joint ESA-NASA class-M mission proposed in response to the last ESA Call for the Cosmic Vision 2015-2025 planning cycle (launch in 2017). SPACE will produce the largest three-dimensional evolutionary map of the Universe over the past 10 billion years by taking near-IR (0.8-1.8micron) spectra at R=400 of more than 0.510^9 galaxies down to AB~23 over the 3pi sr of sky unobscured by the Galaxy. SPACE will precisely locate (Dz~0.001) each galaxy and observe baryonic acoustic oscillation (BAO) patterns in the Universe between 5 to 10 billion years ago, improving the figure of merit for knowledge of dark energy by more than an order of magnitude. The same dataset will simultaneously allow an accurate assessment of the evolution of structure formation over the last 10 billion years, providing a complementary method to discriminate between theories of dark energy and theories of modified gravity proposed to explain the acceleration of the universe. The spectroscopic catalogue of more than a half billion galaxies out to redshift z≈2 will be used for a wide range of investigations into the formation, evolution, and interaction of galaxies in the Universe.
Galaxy Merger at z>1 in the HUDF: Evidence for a Peak in the Major Merger Rate
Russell Ryan (Arizona State University)
We present a measurement of the galaxy merger fraction and number density from observations in the Hubble Ultra-Deep Field for 0.51. We show that the merger number density peaks at z_{dens}~1.3, which marks the epoch where major merging of massive galaxies is most prevalent. This critical redshift is comparable to the peak of the cosmic star formation rate density, and occurs roughly 2.5 Gyr earlier in cosmic time than the peak of the X-ray active galactic nuclei density. Our observations support an indirect evolutionary link between merging, starburst, and active galaxies.
Use of Tools of Nonlinear Dynamical Theory and Numerical Simulation in Understanding Stellar Interiors
Dr.  Eeshankur Saikia (Inderprastha Engineering College)
Tools of Nonlinear Dynamical Theory are used in astrophysics in the form of techniques for extracting information from various time series. Analysis of a time series without losing the important information hidden within, still poses as a challenge. This is more so when the time series obtained from the physical phenomenon is either short (involving very few data-points) or having varying frequency. The talk would emphasise on the effective use of the tools such as Correlation Dimension and Lyapunov Exponent in analyzing an astrophysical time series. Besides, it is believed that the numerical simulation is an inevitable tool in near future to understand various astrophysical phenomena as the theoretical development is inadequate and observational tools are always going to be economically non-viable and time consuming. Use of simulation techniques and available computational resources vis-a-vis astrophysical phenomenon such as stellar convection will be highlighted in the paper.
The Inhomogeneous Background of H2 Dissociating Radiation During Cosmic Reionization
Prof.  Paul Shapiro (The University of Texas at Austin)
See Poster.
Simulating Reionization and Its Observability
Prof.  Paul Shapiro (The University of Texas at Austin)
See Poster.
Does Radiative Feedback by the First Stars Promote or Prevent Second Generation Star Formation?
Prof.  Paul Shapiro (The University of Texas at Austin)
See Poster.
The 21-cm Signature of the Early Radiation Sources
Prof.  Paul Shapiro (The University of Texas at Austin)
See Poster.
Detecting 3.3 Micron PAH Emission with Broadband Photometry: Implications for JWST detections of Organic Molecules at High Redshift
Dr.  Brian Siana (Spitzer Science Center)
We outline our current research detecting the PAH emission feature at 3.3 Microns with IRAC photometry in the GOODS fields. We then discuss the possibility of detecting these organic molecules out to z~6 with JWST.
Solar System Science With JWST
Dr.  George Sonneborn (NASA/GSFC)
JWST will enable breakthroughs in our understanding of the physical characteristics of cold bodies in the outer reaches of the Solar System. These objects include Pluto and other Kuiper Belt Objects (KBOs), the icy moons of the giant planets, and distant cometary nuclei. Recent discoveries of large objects in the Kuiper belt, along with many smaller members, make it clear that this region represents a major constituent of our Solar System, one that was hidden until recently because it is so remote and challenging to observe. The near-IR and mid-IR performance of JWST will be unique in its power to probe this region. This poster describes the science drivers for JWST observations of Solar System objects and plans for implementing this capability.
A strategy to study First Light with JWST
Dr.  Massimo Stiavelli (Space Telescope Science Institute)
We show how we expect that JWST will be needed to study first light despite the expected future progress in this field. We outline a viable strategy to identify and confirm first galaxies using JWST.
Studying Resolved Stellar Populations with the James Webb Space Telescope
Dr.  Massimo Stiavelli (Space Telescope Science Institute)
The James Webb Space Telescope (JWST) will make important contributions to studies of stellar populations in nearby galaxies, including our own. JWST observations will contribute to: (1) the study of the star formation histories of nearby galaxies, exploiting the large lever arm provided by visible-infrared colors; (2) the derivation of the properties of stellar populations from the study of the bright red stellar component out to the Virgo cluster and beyond; and (3) the derivation of the white dwarf cooling sequence age of globular clusters in the Milky Way from the study of deep visible red color magnitude diagrams.
The Spitzer Warm Mission: Hot Science with a "Warm" Telescope
Dr.  Lisa Storrie-Lombardi (Spitzer Science Center, Caltech)
The Spitzer Space Telescope is the infrared component of NASA's family of Great Observatories. In approximately March 2009 the liquid Helium cryogen on board Spitzer will be exhausted but the observatory will remain operative with 3.6 and 4.5 micron imaging capabilities over two 5'x5' fields-of-view. Sensitivity in these channels will remain unchanged from the cryogenic mission. In this "warm mission" phase Spitzer can operate until ~2014 with high-efficiency providing up to 35,000 hours of science observing time. This enables several unprecedented opportunities to address fundamental scientific questions requiring large allocations of observing time, while maintaining opportunities for broad community use with more traditional time allocations. This poster summarizes some of the possible large scientific programs enabled by a Spitzer warm mission, including support for theory and archival programs. The content is summarized from contributed white papers to the Spitzer Warm Mission workshop held in Pasadena, CA in June 2007 (Http://ssc.spitzer.caltech.edu/mtgs/warm/). The proceedings will be published this fall by AIP.
Emission Line Galaxies in PEARS: A 2-D Detection Method
Amber Straughn (Arizona State University)
The PEARS (Probing Evolution And Reionization Spectroscopically) project provides an enormous dataset of low-resolution spectra from thousands of galaxies in the GOODS North and South fields. Here we present results of a search for emission line galaxies in PEARS using a unique 2D detection method that utilizes the observation that many emission lines originate from clumpy knots within galaxies (Meurer 2005). This 2D line-finding method proves to be useful in detecting emission lines from compact knots within galaxies that might not otherwise be detected using more traditional 1D line-finding techniques. Preliminary results in the Hubble Ultra Deep Field indicate that 5% of galaxies--79 in total--to 27 mag display prominant emission lines. 14% of these 79 galaxies display a merging/interacting morphology. Completion of the remaining ACS fields will result in a catalog of 600-900 emission line sources. From these line emitters we can derive the luminosity function of [OII] and [OIII] lines at z= 0.5-1.
GOODS 850-5 --- An Example of Optically Faint Dusty Galaxy at High Redshift
Dr.  Wei-Hao Wang (NRAO)
We report a Submillimeter Array (SMA) interferometric identification of a bright submillimeter (submm) source, GOODS 850-5. This source is only bright at 850 um but is extremely faint at all other wavelengths. It is not detected in the GOODS HST ACS images and only shows a weak 2 ? signal at 1.4 GHz. It is detected in the Spitzer IRAC bands and the MIPS 24 um band, however, with very low fluxes. Evidence in the radio, submm, mid-IR, near-IR, and optical suggests that GOODS 850-5 is a galaxy at z > 4. Submm sources like GOODS 850-5 can contribute significantly to the cosmic star formation history but are almost entirely missed by existing surveys. Complete studies of optically faint galaxies like GOODS 850-5 are a great challenge to current instruments, and require next-generation telescopes at all wavelengths such as the JWST, EVLA, and ALMA.
Technical aspects of how the James Webb Space Telescope can measure First Light, Reionization, and Galaxy Assembly
Dr.  Rogier Windhorst (Arizona State University)
We review the technical aspects of how the 6.5 meter James Webb Space Telescope (JWST) can measure First Light, Reionization, Galaxy Assembly (see Stiavelli etal. and other posters), building on lessons learned from the Hubble Space Telescope (HST). We show what combination of area, depth, and wavelength coverage are needed for JWST to detect a sufficient number of First Light objects, and to measure their evolving luminosity function (LF). In detail, JWST will map the epoch of First light through Pop III star dominated objects at redshifts z=8-20, and its transition to the first Pop II stars in dwarf galaxies. The expected steep faint-end of the dwarf galaxy LF at redshifts z=6-7 likely provided the UV-flux needed to finish reionization. We discuss: 1) what deep JWST images will look like compared to the Hubble UltraDeep Field (HUDF), given JWST's expected PSF performance; (2) simulations of what nearby galaxies observed in their restframe UV-optical light by HST would look like to JWST at very high redshifts; (3) quantitative methods to determine structural parameters of faint galaxies in deep JWST images as a function of cosmic epoch to delineate the progress of galaxy assembly; (4) to what extent JWST's short-wavelength performance --- which needed to be relaxed in the 2005 redefinition of the telescope --- will affect JWST's ability to accurately determine faint galaxy parameters; and (5) if ultradeep JWST images will run into the instrumental and natural confusion limits. A new generations of algorithms may be needed to automatically detect, measure and classify objects in very crowded, ultradeep JWST fields. We demonstrate an interactive web-tool on a laptop that lets the user pan and zoom 3-D through the HUDF data-base from redshifts z=0 to z=6, with all galaxy images sorted versus spectro-photometric redshift, and visualize what JWST will add from AB=29.5-32.0 mag and between redshifts z=7-20. This work was funded by NASA JWST Interdisciplinary Scientist grant NAG5-12460 from GSFC, and grant HST/ED14-975 from STScI, which is operated by AURA for NASA under contract NAS5-26555.
The Atacama Large Millimeter Array: Recent Progress, Specifications and Science Goals
Dr.  Alwyn Wootten (National Radio Astronomy Observatory)
The 12m antennas have been purchased, with both North America and Europe placing a contract for at least 25, and Japan having contracted for their first 4. These antennas are the highest precision radio telescopes ever built. The first two North American and the first three Japanese production antennas are on the ALMA site. Two prototypes at the ALMA Test Facility (ATF) in Socorro, NM (upper right) have successfully demonstrated interferometry with a prototype system. Construction of the technical building (TB) on the 16,500-foot elevation Array Operations Site (AOS) has been completed, on time and below budget. Construction at the mid-level Operations Support Facility is nearing completion (Jan 2008). Prototype receivers all meet specifications, near quantum-limit noise, unprecedented bandwidth, and require no mechanical tuning. The first receiver package is entering final tests at the NRAO Technology Center in Charlottesville. The first quadrant of the ALMA correlator is complete and under test. Blazingly fast in its single-minded functionality, the complete correlator will achieve greater than 1016 floating point operations per second. It will be installed in the AOS TB later in 2007. ALMA Regional Science Centers in North America, Europe and East Asia have been organized.
The JWST Mid-Infrared Instrument Capabilities and Current Status
Dr.  Gillian Wright (UK Astronomy Technology Centre)
The poster will summarise MIRI capabilities of interest to conference attendees - photometric imaging bands, spectral resolutions, coronagraphs, sensitivities etc. We will also summarise the current status.