Search Publications
Physical Properties and Galactic Distribution of Molecular Clouds Identified in the Galactic Ring Survey
Jackson, James M.; Roman-Duval, Julia; Heyer, Mark +2 more
We derive the physical properties of 580 molecular clouds based on their 12CO and 13CO line emission detected in the University of Massachusetts-Stony Brook (UMSB) and Galactic Ring surveys. We provide a range of values of the physical properties of molecular clouds, and find a power-law correlation between their radii and ma…
Discovery of z ~ 8 Galaxies in the Hubble Ultra Deep Field from Ultra-Deep WFC3/IR Observations
Trenti, M.; Oesch, P. A.; Carollo, C. M. +8 more
We utilize the newly acquired, ultra-deep WFC3/IR observations over the Hubble Ultra Deep Field (HUDF) to search for star-forming galaxies at z ~ 8-8.5, only 600 million years from recombination, using a Y 105-dropout selection. The new 4.7 arcmin2 WFC3/IR observations reach to ~28.8 AB mag (5σ) in the Y 105 J
The Third US Naval Observatory CCD Astrograph Catalog (UCAC3)
Zacharias, N.; Girard, T.; Makarov, V. +27 more
The third US Naval Observatory (USNO) CCD Astrograph Catalog, UCAC3, was released at the IAU General Assembly on 2009 August 10. It is the first all-sky release in this series and contains just over 100 million objects, about 95 million of them with proper motions, covering about R = 8-16 mag. Current epoch positions are obtained from the observat…
Evidence of the accelerated expansion of the Universe from weak lensing tomography with COSMOS
Benabed, K.; Simon, P.; Schrabback, T. +19 more
We present a comprehensive analysis of weak gravitational lensing by large-scale structure in the Hubble Space Telescope Cosmic Evolution Survey (COSMOS), in which we combine space-based galaxy shape measurements with ground-based photometric redshifts to study the redshift dependence of the lensing signal and constrain cosmological parameters. Af…
The ACS Nearby Galaxy Survey Treasury. IX. Constraining Asymptotic Giant Branch Evolution with Old Metal-poor Galaxies
Williams, Benjamin F.; Gilbert, Karoline M.; Boyer, Martha L. +10 more
In an attempt to constrain evolutionary models of the asymptotic giant branch (AGB) phase at the limit of low masses and low metallicities, we have examined the luminosity functions and number ratios between AGB and red giant branch (RGB) stars from a sample of resolved galaxies from the ACS Nearby Galaxy Survey Treasury. This database provides Hu…
The Luminosity and Mass Functions of Low-mass Stars in the Galactic Disk. II. The Field
Hawley, Suzanne L.; Golimowski, David A.; Reid, I. Neill +4 more
We report on new measurements of the luminosity function (LF) and mass function (MF) of field low-mass dwarfs derived from Sloan Digital Sky Survey Data Release 6 photometry. The analysis incorporates ~15 million low-mass stars (0.1 {\cal M}_\odot {\cal M} < 0.8\,{\cal M}_\odot), spread over 8400 deg2. Stellar distances are estimated…
Quantifying Quasar Variability as Part of a General Approach to Classifying Continuously Varying Sources
Soszyński, I.; Udalski, A.; Szymański, M. K. +9 more
Robust fast methods to classify variable light curves in large sky surveys are becoming increasingly important. While it is relatively straightforward to identify common periodic stars and particular transient events (supernovae, novae, microlensing events), there is no equivalent for non-periodic continuously varying sources (quasars, aperiodic s…
Evaporation of the planet HD 189733b observed in H I Lyman-α
Ehrenreich, D.; Udry, S.; Ferlet, R. +7 more
We observed three transits of the extrasolar planet HD 189733b in H i Lyman-α and in a few other lines in the ultraviolet with HST/ACS, in the search for atmospheric signatures. We detect a transit signature in the Lyman-α light curve with a transit depth of 5.05 ± 0.75%. This depth exceeds the occultation depth produced by the planetary disk alon…
The Calibration of Monochromatic Far-Infrared Star Formation Rate Indicators
Moustakas, J.; Murphy, E. J.; Walter, F. +23 more
Spitzer data at 24, 70, and 160 µm and ground-based Hα images are analyzed for a sample of 189 nearby star-forming and starburst galaxies to investigate whether reliable star formation rate (SFR) indicators can be defined using the monochromatic infrared dust emission centered at 70 and 160 µm. We compare recently published recipes for…
On the Cosmic Evolution of the Scaling Relations Between Black Holes and Their Host Galaxies: Broad-Line Active Galactic Nuclei in the zCOSMOS Survey
Kneib, J. -P.; Taniguchi, Y.; Jahnke, K. +56 more
We report on the measurement of the physical properties (rest-frame K-band luminosity and total stellar mass) of the hosts of 89 broad-line (type-1) active galactic nuclei (AGNs) detected in the zCOSMOS survey in the redshift range 1 < z < 2.2. The unprecedented multi-wavelength coverage of the survey field allows us to disentangle the emiss…