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The ACS Fornax Cluster Survey. I. Introduction to the Survey and Data Reduction Procedures
Jordán, Andrés; Infante, Leopoldo; Tonry, John L. +7 more
The Fornax Cluster is a conspicuous cluster of galaxies in the southern hemisphere and the second largest collection of early-type galaxies within <~20 Mpc after the Virgo Cluster. In this paper, we present a brief introduction to the ACS Fornax Cluster Survey-a program to image, in the F475W (g475) and F850LP (z850) bandp…
Abundances and Behavior of 12CO, 13CO, and C2 in Translucent Sight Lines
York, D. G.; Sonnentrucker, P.; Welty, D. E. +1 more
Using UV spectra obtained with FUSE, HST, and/or IUE together with higher resolution optical spectra, we determine interstellar column densities of 12CO, 13CO, and/or C2 for 10 Galactic sight lines with E(B-V) ranging from 0.37 to 0.72. The N(CO)/N(H2) ratio varies over a factor of 100 in this sample, d…
The Stability of the Point-Spread Function of the Advanced Camera for Surveys on the Hubble Space Telescope and Implications for Weak Gravitational Lensing
Gardner, Jonathan P.; Ellis, Richard S.; Leauthaud, Alexie +11 more
We examine the spatial and temporal stability of the Hubble Space Telescope's Advanced Camera for Surveys (ACS) Wide Field Camera (WFC) point-spread function (PSF) using the 2 deg2 COSMOS survey. This is important for studies of weak gravitational lensing, where the ability to deconvolve the PSF from galaxy shapes is of paramount import…
The XMM-Newton Wide-Field Survey in the COSMOS Field. II. X-Ray Data and the logN-logS Relations
Finoguenov, A.; Böhringer, H.; Fiore, F. +13 more
We present data analysis and X-ray source counts for the first season of XMM-Newton observations in the COSMOS field. The survey covers ~2 deg2 within the region of sky bounded by 09h57m30s<R.A.<10h03m30s, 01deg27'30''<decl.<02…
The Effects of Environment on Morphological Evolution at 0<z<1.2 in the COSMOS Survey
Mobasher, Bahram; Ellis, Richard S.; Capak, Peter +4 more
We explore the evolution of the morphology-density relation using the COSMOS Advanced Camera for Surveys (ACS) and previous cluster studies. The Gini parameter measured in a Petrosian aperture is found to be an effective way of selecting early-type galaxies free from systematic effects with redshift. We find that galaxies are transformed from late…
The Cosmic Evolution Survey (COSMOS): The Morphological Content and Environmental Dependence of the Galaxy Color-Magnitude Relation at z ~ 0.7
Taniguchi, Y.; Franceschini, A.; Capak, P. +11 more
We study the environmental dependence and the morphological composition of the galaxy color-magnitude diagram at z~0.7, using a pilot subsample of COSMOS. The sample includes ~2000 galaxies with IAB<24 and photometric redshift within 0.61<z<0.85, covering an area of 270 arcmin2. Galaxy morphologies are estimated via …
Search for Polarization from the Prompt Gamma-Ray Emission of GRB 041219a with SPI on INTEGRAL
Kouveliotou, C.; Baring, M. G.; Boggs, S. E. +2 more
Measuring the polarization of the prompt γ-ray emission from gamma-ray bursts (GRBs) can significantly improve our understanding of both the GRB emission mechanisms as well as the underlying engine driving the explosion. We searched for polarization in the prompt γ-ray emission of GRB 041219a with the SPI instrument on INTEGRAL. Using multiple-det…
The Evolution of the Number Density of Large Disk Galaxies in COSMOS
Kneib, J. -P.; Taniguchi, Y.; Sargent, M. T. +17 more
We study a sample of approximately 16,500 galaxies with IACS,AB<=22.5 in the central 38% of the COSMOS field, which are extracted from a catalog constructed from the Cycle 12 ACS F814W COSMOS data set. Structural information on the galaxies is derived by fitting single Sérsic models to their two-dimensional surface brightness distrib…
The XMM-Newton Wide-Field Survey in the COSMOS Field. IV. X-Ray Spectral Properties of Active Galactic Nuclei
Finoguenov, A.; Taniguchi, Y.; Fiore, F. +25 more
We present a detailed spectral analysis of pointlike X-ray sources in the XMM-Newton COSMOS field. Our sample of 135 sources only includes those that have more than 100 net counts in the 0.3-10 keV energy band and have been identified through optical spectroscopy. The majority of the sources are well described by a simple power-law model with eith…
The Intrinsically X-Ray-weak Quasar PHL 1811. II. Optical and UV Spectra and Analysis
Jenkins, Edward B.; Halpern, Jules P.; Leighly, Karen M. +1 more
This is the second of two papers reporting observations and analysis of the unusually bright (mb=14.4), luminous (MB=-25.5), nearby (z=0.192) narrow-line quasar PHL 1811. The first paper reported that PHL 1811 is intrinsically X-ray-weak and presented a spectral energy distribution (SED). Here we present HST STIS optical and …