Search Publications
Direct Measurements of Dust Attenuation in z ~ 1.5 Star-forming Galaxies from 3D-HST: Implications for Dust Geometry and Star Formation Rates
van Dokkum, Pieter G.; Franx, Marijn; Conroy, Charlie +11 more
The nature of dust in distant galaxies is not well understood, and until recently few direct dust measurements have been possible. We investigate dust in distant star-forming galaxies using near-infrared grism spectra of the 3D-HST survey combined with archival multi-wavelength photometry. These data allow us to make a direct comparison between du…
Systematic Uncertainties Associated with the Cosmological Analysis of the First Pan-STARRS1 Type Ia Supernova Sample
Price, P. A.; Berger, E.; Challis, P. +46 more
We probe the systematic uncertainties from the 113 Type Ia supernovae (SN Ia) in the Pan-STARRS1 (PS1) sample along with 197 SN Ia from a combination of low-redshift surveys. The companion paper by Rest et al. describes the photometric measurements and cosmological inferences from the PS1 sample. The largest systematic uncertainty stems from the p…
Star Formation at 4 < z < 6 from the Spitzer Large Area Survey with Hyper-Suprime-Cam (SPLASH)
Strauss, Michael A.; Capak, Peter; Scoville, Nick +21 more
Using the first 50% of data collected for the Spitzer Large Area Survey with Hyper-Suprime-Cam observations on the 1.8 deg2 Cosmological Evolution Survey we estimate the masses and star formation rates of 3398 M * > 1010 M ⊙ star-forming galaxies at 4 < z < 6 with a substantial population up to …
Short GRB 130603B: Discovery of a Jet Break in the Optical and Radio Afterglows, and a Mysterious Late-time X-Ray Excess
Berger, E.; Foley, R. J.; Chornock, R. +13 more
We present radio, optical/NIR, and X-ray observations of the afterglow of the short-duration Swift and Konus-Wind GRB 130603B, and uncover a break in the radio and optical bands at ≈0.5 day after the burst, best explained as a jet break with an inferred jet opening angle of ≈4°-8°. GRB 130603B is only the third short GRB with a radio afterglow det…
Charting the Evolution of the Ages and Metallicities of Massive Galaxies since z = 0.7
Bell, Eric F.; Brinchmann, Jarle; Kelson, Daniel D. +2 more
Detailed studies of the stellar populations of intermediate-redshift galaxies can shed light onto the processes responsible for the growth of the massive galaxy population in the last 8 billion years. We here take a step toward this goal by means of deep, multiobject rest-frame optical spectroscopy, performed with the Inamori Magellan Areal Camera…
Spectroscopic Confirmation of the Rich z = 1.80 Galaxy Cluster JKCS 041 using the WFC3 Grism: Environmental Trends in the Ages and Structure of Quiescent Galaxies
Treu, Tommaso; Trinchieri, Ginevra; Ellis, Richard S. +3 more
We present Hubble Space Telescope imaging and grism spectroscopy in the field of the distant galaxy cluster JKCS 041 using the Wide Field Camera 3. We confirm that JKCS 041 is a rich cluster and derive a redshift z = 1.80 via the spectroscopic identification of 19 member galaxies, of which 15 are quiescent. These are centered upon diffuse X-ray em…
Geometry of Star-forming Galaxies from SDSS, 3D-HST, and CANDELS
Ferguson, H. C.; Giavalisco, M.; Brammer, G. +18 more
We determine the intrinsic, three-dimensional shape distribution of star-forming galaxies at 0 < z < 2.5, as inferred from their observed projected axis ratios. In the present-day universe, star-forming galaxies of all masses 109-1011 M ⊙ are predominantly thin, nearly oblate disks, in line with previous stud…
The Star Formation Histories of Local Group Dwarf Galaxies. II. Searching For Signatures of Reionization
Dolphin, Andrew E.; Skillman, Evan D.; Williams, Benjamin F. +4 more
We search for signatures of reionization in the star formation histories (SFHs) of 38 Local Group dwarf galaxies (104 < M sstarf < 109 M ⊙). The SFHs are derived from color-magnitude diagrams using archival Hubble Space Telescope/Wide Field Planetary Camera 2 imaging. Only five quenched galaxies (A…
Magnetic Fields in Relativistic Collisionless Shocks
Santana, Rodolfo; Barniol Duran, Rodolfo; Kumar, Pawan
We present a systematic study on magnetic fields in gamma-ray burst (GRB) external forward shocks (FSs). There are 60 (35) GRBs in our X-ray (optical) sample, mostly from Swift. We use two methods to study epsilon B (fraction of energy in magnetic field in the FS): (1) for the X-ray sample, we use the constraint that the observed flux …
CANDELS+3D-HST: Compact SFGs at z ~ 2-3, the Progenitors of the First Quiescent Galaxies
Wuyts, S.; Giavalisco, M.; Papovich, C. +34 more
We analyze the star-forming and structural properties of 45 massive (log(M/M ⊙) >10) compact star-forming galaxies (SFGs) at 2 < z < 3 to explore whether they are progenitors of compact quiescent galaxies at z ~ 2. The optical/NIR and far-IR Spitzer/Herschel colors indicate that most compact SFGs are heavily obscured. Nearly ha…