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PHAT Stellar Cluster Survey. I. Year 1 Catalog and Integrated Photometry
DOI: 10.1088/0004-637X/752/2/95 Bibcode: 2012ApJ...752...95J

Monachesi, Antonela; Gouliermis, Dimitrios A.; Dolphin, Andrew E. +21 more

The Panchromatic Hubble Andromeda Treasury (PHAT) survey is an ongoing Hubble Space Telescope (HST) multi-cycle program to obtain high spatial resolution imaging of one-third of the M31 disk at ultraviolet through near-infrared wavelengths. In this paper, we present the first installment of the PHAT stellar cluster catalog. When completed, the PHA…

2012 The Astrophysical Journal
eHST 71
Revision of Solar Spicule Classification
DOI: 10.1088/0004-637X/750/1/16 Bibcode: 2012ApJ...750...16Z

Liu, Y.; Su, J. T.; Wang, J. X. +4 more

Solar spicules are the fundamental magnetic structures in the chromosphere and may play a key role in channeling the chromosphere and corona. Recently, it was suggested by De Pontieu et al. that there were two types of spicules with very different dynamic properties, which were detected by the space-time plot technique in the Ca II H line (3968 Å)…

2012 The Astrophysical Journal
Hinode 71
Clustering Properties of BzK-selected Galaxies in GOODS-N: Environmental Quenching and Triggering of Star Formation at z ~ 2
DOI: 10.1088/0004-637X/756/1/71 Bibcode: 2012ApJ...756...71L

Dickinson, Mark; Grogin, Norman A.; Yan, Chi-Hung +19 more

Using a sample of BzK-selected galaxies at z ~ 2 identified from the CFHT/WIRCAM near-infrared survey of GOODS-North, we discuss the relation between star formation rate (SFR), specific star formation rate (SSFR), and stellar mass (M *), and the clustering of galaxies as a function of these parameters. For star-forming galaxies (sBzKs),…

2012 The Astrophysical Journal
eHST 71
Automatically Detecting and Tracking Coronal Mass Ejections. I. Separation of Dynamic and Quiescent Components in Coronagraph Images
DOI: 10.1088/0004-637X/752/2/144 Bibcode: 2012ApJ...752..144M

Morgan, Huw; Habbal, Shadia Rifai; Byrne, Jason P.

Automated techniques for detecting and tracking coronal mass ejections (CMEs) in coronagraph data are of ever increasing importance for space weather monitoring and forecasting. They serve to remove the biases and tedium of human interpretation, and provide the robust analysis necessary for statistical studies across large numbers of observations.…

2012 The Astrophysical Journal
SOHO 71
Broad-line Region Physical Conditions in Extreme Population A Quasars: A Method to Estimate Central Black Hole Mass at High Redshift
DOI: 10.1088/0004-637X/757/1/62 Bibcode: 2012ApJ...757...62N

Sulentic, Jack W.; Marziani, Paola; Negrete, C. Alenka +1 more

We describe a method for estimating physical conditions in the broad-line region (BLR) for a significant subsample of Seyfert 1 nuclei and quasars. Several diagnostic ratios based on intermediate (Al III λ1860, Si III] λ1892) and high (C IV λ1549, Si IV λ1397) ionization lines in the UV spectra of quasars are used to constrain density, ionization,…

2012 The Astrophysical Journal
eHST 71
Unmasking the Supernova Impostors
DOI: 10.1088/0004-637X/758/2/142 Bibcode: 2012ApJ...758..142K

Kochanek, C. S.; Stanek, K. Z.; Szczygieł, D. M.

The canonical picture of a supernova impostor is a short (~months) -11 <~ MV <~ -14 optical transient from a massive (M * >~ 40 M ) star during which the star ejects a dense shell of material. Dust formed in the ejecta then obscures the star. In this picture, the geometric expansion of the shell leads to …

2012 The Astrophysical Journal
eHST 70
The Optically Unbiased GRB Host (TOUGH) Survey. V. VLT/X-shooter Emission-line Redshifts for Swift GRBs at z ~ 2
DOI: 10.1088/0004-637X/758/1/46 Bibcode: 2012ApJ...758...46K

Hjorth, Jens; Fynbo, Johan P. U.; Milvang-Jensen, Bo +7 more

We present simultaneous optical and near-infrared (NIR) spectroscopy of 19 Swift γ-ray burst (GRB) host galaxies observed with the VLT/X-shooter with the aim of measuring their redshifts. Galaxies were selected from The Optically Unbiased GRB Host (TOUGH) survey (15 of the 19 galaxies) or because they hosted GRBs without a bright optical afterglow…

2012 The Astrophysical Journal
eHST 70
Spectral Energy Distributions of Type 1 Active Galactic Nuclei in the COSMOS Survey. I. The XMM-COSMOS Sample
DOI: 10.1088/0004-637X/759/1/6 Bibcode: 2012ApJ...759....6E

Liu, Y.; Aussel, H.; Le Floc'h, E. +39 more

The "Cosmic Evolution Survey" (COSMOS) enables the study of the spectral energy distributions (SEDs) of active galactic nuclei (AGNs) because of the deep coverage and rich sampling of frequencies from X-ray to radio. Here we present an SED catalog of 413 X-ray (XMM-Newton)-selected type 1 (emission line FWHM > 2000 km s-1) AGNs with …

2012 The Astrophysical Journal
eHST 70
Weak Lensing Measurement of Galaxy Clusters in the CFHTLS-Wide Survey
DOI: 10.1088/0004-637X/748/1/56 Bibcode: 2012ApJ...748...56S

Massey, Richard; Kneib, Jean-Paul; Rhodes, Jason +7 more

We present the first weak gravitational lensing analysis of the completed Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). We study the 64 deg2 W1 field, the largest of the CFHTLS-Wide survey fields, and present the largest contiguous weak lensing convergence "mass map" yet made. 2.66 million galaxy shapes are measured, using the …

2012 The Astrophysical Journal
eHST 70
The Slow Death (Or Rebirth?) of Extended Star Formation in z ~ 0.1 Green Valley Early-type Galaxies
DOI: 10.1088/0004-637X/761/1/23 Bibcode: 2012ApJ...761...23F

Faber, S. M.; Salim, Samir; Rich, R. Michael +2 more

UV observations in the local universe have uncovered a population of early-type galaxies with UV flux consistent with low-level recent or ongoing star formation. Understanding the origin of such star formation remains an open issue. We present resolved UV-optical photometry of a sample of 19 Sloan Digital Sky Survey (SDSS) early-type galaxies at z…

2012 The Astrophysical Journal
eHST 70