Search Publications
Resolved spectroscopy of gravitationally lensed galaxies: recovering coherent velocity fields in subluminous z ~ 2-3 galaxies
Swinbank, A. M.; Richard, J.; Stark, D. P. +2 more
We present spatially resolved dynamics for six strongly lensed star-forming galaxies at z = 1.7-3.1, each enlarged by a linear magnification factor of ~×8. Using the Keck laser guide star AO system and the OH-Suppressing Infra-Red Imaging Spectrograph integral field unit spectrograph, we resolve kinematic and morphological detail in our sample wit…
Survey of ion plasma parameters in Saturn's magnetosphere
Thomsen, M. F.; Tokar, R. L.; Reisenfeld, D. B. +6 more
A survey of the bulk plasma ion properties observed by the Cassini Plasma Spectrometer instrument over roughly the first 4.5 years of its mission in orbit around Saturn is presented. The moments (density, temperature, and flow velocity) of the plasma distributions below 50 keV have been computed by numerical integration of the observed counts in t…
Hubble/COS Observations of the Lyα Forest Toward the BL Lac Object 1ES 1553+113
Shull, J. Michael; Danforth, Charles W.; Stocke, John T. +2 more
We present new moderate-resolution, far-ultraviolet spectra from the Hubble Space Telescope/Cosmic Origins Spectrograph (HST/COS) of the BL Lac object 1ES 1553+113 covering the wavelength range 1135 Å < λ < 1795 Å. The data show a smooth continuum with a wealth of narrow (b < 100 km s-1) absorption features arising in the inter…
Discovery of Precursor Luminous Blue Variable Outbursts in Two Recent Optical Transients: The Fitfully Variable Missing Links UGC 2773-OT and SN 2009ip
Ghez, Andrea M.; Filippenko, Alexei V.; Smith, Nathan +11 more
We present progenitor-star detections, light curves, and optical spectra of supernova (SN) 2009ip and the 2009 optical transient in UGC 2773 (U2773-OT), which were not genuine SNe. Precursor variability in the decade before outburst indicates that both of the progenitor stars were luminous blue variables (LBVs). Their pre-outburst light curves res…
On the Stellar Populations and Evolution of Star-forming Galaxies at 6.3 < z <= 8.6
Papovich, Casey; Finkelstein, Steven L.; Dickinson, Mark +4 more
Observations of very distant galaxies probe both the formation and evolution of galaxies, and also the nature of the sources responsible for reionizing the intergalactic medium (IGM). Here, we study the physical characteristics of galaxies at 6.3 < z <= 8.6, selected from deep near-infrared imaging with the Wide Field Camera 3 (WFC3) on boar…
Red-giant seismic properties analyzed with CoRoT
Auvergne, M.; Goupil, M. -J.; Baudin, F. +10 more
Context. The CoRoT 5-month long observation runs provide us with the opportunity to analyze a large variety of red-giant stars and derive their fundamental parameters from their asteroseismic properties.
Aims: We perform an analysis of more than 4600 CoRoT light curves to extract as much information as possible. We take into account the chara…
The Antennae Galaxies (NGC 4038/4039) Revisited: Advanced Camera for Surveys and NICMOS Observations of a Prototypical Merger
Leitherer, Claus; Whitmore, Bradley C.; Chandar, Rupali +7 more
The Advanced Camera for Surveys and the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) have been used to obtain new Hubble Space Telescope images of NGC 4038/4039 ("The Antennae"). These new observations allow us to better differentiate compact star clusters from individual stars, based on both size and color. We use this ability to e…
In-flight calibration of the Herschel-SPIRE instrument
Aussel, H.; Valtchanov, I.; Savini, G. +55 more
SPIRE, the Spectral and Photometric Imaging REceiver, is the Herschel Space Observatory's submillimetre camera and spectrometer. It contains a three-band imaging photometer operating at 250, 350 and 500 µm, and an imaging Fourier-transform spectrometer (FTS) covering 194-671 µm (447-1550 GHz). In this paper we describe the initial appr…
An Atlas of z = 5.7 and z = 6.5 Lyα Emitters
Capak, P.; Barger, A. J.; Cowie, L. L. +3 more
We present an atlas of 88 z ~ 5.7 and 30 z ~ 6.5 Lyα emitters obtained from a wide-field narrowband survey. We combined deep narrowband imaging in 120 Å bandpass filters centered at 8150 Å and 9140 Å with deep BVRIz broadband imaging to select high-redshift galaxy candidates over an area of 4180 arcmin2. The goal was to obtain a uniform…
Color-Magnitude Relations of Active and Non-active Galaxies in the Chandra Deep Fields: High-redshift Constraints and Stellar-mass Selection Effects
Lehmer, B. D.; Alexander, D. M.; Silverman, J. D. +6 more
We extend color-magnitude relations for moderate-luminosity X-ray active galactic nucleus (AGN) hosts and non-AGN galaxies through the galaxy formation epoch (z ≈ 1-4) in the Chandra Deep Field-North and Chandra Deep Field-South (CDF-N and CDF-S, respectively; jointly CDFs) surveys. This study was enabled by the deepest available X-ray data from t…