Search Publications

The Epoch of Disk Settling: z ~ 1 to Now
DOI: 10.1088/0004-637X/758/2/106 Bibcode: 2012ApJ...758..106K

Weiner, Benjamin J.; Gardner, Jonathan P.; Faber, S. M. +11 more

We present evidence from a sample of 544 galaxies from the DEEP2 Survey for evolution of the internal kinematics of blue galaxies with stellar masses ranging 8.0 < log M *(M ) < 10.7 over 0.2 < z < 1.2. DEEP2 provides galaxy spectra and Hubble imaging from which we measure emission-line kinematics and galaxy incl…

2012 The Astrophysical Journal
eHST 210
The Type IIb Supernova 2011dh from a Supergiant Progenitor
DOI: 10.1088/0004-637X/757/1/31 Bibcode: 2012ApJ...757...31B

Nomoto, Ken'ichi; Fraser, Morgan; Sollerman, Jesper +10 more

A set of hydrodynamical models based on stellar evolutionary progenitors is used to study the nature of SN 2011dh. Our modeling suggests that a large progenitor star—with R ~ 200 R —is needed to reproduce the early light curve (LC) of SN 2011dh. This is consistent with the suggestion that the yellow super-giant star detected at the loc…

2012 The Astrophysical Journal
eHST 209
Evidence for a Clumpy, Rotating Gas Disk in a Submillimeter Galaxy at z = 4
DOI: 10.1088/0004-637X/760/1/11 Bibcode: 2012ApJ...760...11H

Daddi, E.; Walter, F.; Riechers, D. +4 more

We present Karl G. Jansky Very Large Array observations of the CO(2-1) emission in the z = 4.05 submillimeter galaxy (SMG) GN20. These high-resolution data allow us to image the molecular gas at 1.3 kpc resolution just 1.6 Gyr after the big bang. The data reveal a clumpy, extended gas reservoir, 14 ± 4 kpc in diameter, in unprecedented detail. A d…

2012 The Astrophysical Journal
eHST 209
A Large Population of Massive Compact Post-starburst Galaxies at z > 1: Implications for the Size Evolution and Quenching Mechanism of Quiescent Galaxies
DOI: 10.1088/0004-637X/745/2/179 Bibcode: 2012ApJ...745..179W

van Dokkum, Pieter G.; Franx, Marijn; Labbé, Ivo +4 more

We study the growth of the red sequence through the number density and structural evolution of a sample of young and old quiescent galaxies at 0 < z < 2. The galaxies are selected from the NEWFIRM Medium-Band Survey in the Cosmic Evolution Survey field. We find a large population of massive young recently quenched ("post-starburst") galaxies…

2012 The Astrophysical Journal
eHST 208
Reverberation Mapping Results for Five Seyfert 1 Galaxies
DOI: 10.1088/0004-637X/755/1/60 Bibcode: 2012ApJ...755...60G

Skowron, J.; Kochanek, C. S.; Peterson, B. M. +40 more

We present the results from a detailed analysis of photometric and spectrophotometric data on five Seyfert 1 galaxies observed as a part of a recent reverberation mapping program. The data were collected at several observatories over a 140 day span beginning in 2010 August and ending in 2011 January. We obtained high sampling-rate light curves for…

2012 The Astrophysical Journal
eHST 205
A Unified Empirical Model for Infrared Galaxy Counts Based on the Observed Physical Evolution of Distant Galaxies
DOI: 10.1088/2041-8205/757/2/L23 Bibcode: 2012ApJ...757L..23B

Buat, Véronique; Daddi, Emanuele; Hezaveh, Yashar +10 more

We reproduce the mid-infrared to radio galaxy counts with a new empirical model based on our current understanding of the evolution of main-sequence (MS) and starburst (SB) galaxies. We rely on a simple spectral energy distribution (SED) library based on Herschel observations: a single SED for the MS and another one for SB, getting warmer with red…

2012 The Astrophysical Journal
Herschel 203
CANDELS: The Contribution of the Observed Galaxy Population to Cosmic Reionization
DOI: 10.1088/0004-637X/758/2/93 Bibcode: 2012ApJ...758...93F

Papovich, Casey; Finkelstein, Steven L.; Dickinson, Mark +12 more

We present measurements of the specific ultraviolet luminosity density from a sample of 483 galaxies at 6 <~ z <~ 8. These galaxies were selected from new deep near-infrared Hubble Space Telescope imaging from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, Hubble UltraDeep Field 2009, and Wide Field Camera 3 Early Releas…

2012 The Astrophysical Journal
eHST 201
Modeling the Effects of Star Formation Histories on Hα and Ultraviolet Fluxes in nearby Dwarf Galaxies
DOI: 10.1088/0004-637X/744/1/44 Bibcode: 2012ApJ...744...44W

Skillman, Evan D.; Williams, Benjamin F.; Johnson, L. Clifton +9 more

We consider the effects of non-constant star formation histories (SFHs) on Hα and GALEX far-ultraviolet (FUV) star formation rate (SFR) indicators. Under the assumption of a fully populated Chabrier initial mass function (IMF), we compare the distribution of Hα-to-FUV flux ratios from ~1500 simple, periodic model SFHs with observations of 185 gala…

2012 The Astrophysical Journal
eHST 200
Resolving the Electron Temperature Discrepancies in H II Regions and Planetary Nebulae: κ-distributed Electrons
DOI: 10.1088/0004-637X/752/2/148 Bibcode: 2012ApJ...752..148N

Dopita, Michael A.; Nicholls, David C.; Sutherland, Ralph S.

The measurement of electron temperatures and metallicities in H II regions and planetary nebulae (PNe) has—for several decades—presented a problem: results obtained using different techniques disagree. What is worse, they disagree consistently. There have been numerous attempts to explain these discrepancies, but none has provided a satisfactory s…

2012 The Astrophysical Journal
eHST 196
Fundamental Properties of Stars Using Asteroseismology from Kepler and CoRoT and Interferometry from the CHARA Array
DOI: 10.1088/0004-637X/760/1/32 Bibcode: 2012ApJ...760...32H

Kawaler, S. D.; Thompson, M. J.; Christensen-Dalsgaard, J. +37 more

We present results of a long-baseline interferometry campaign using the PAVO beam combiner at the CHARA Array to measure the angular sizes of five main-sequence stars, one subgiant and four red giant stars for which solar-like oscillations have been detected by either Kepler or CoRoT. By combining interferometric angular diameters, Hipparcos paral…

2012 The Astrophysical Journal
Hipparcos 194