Search Publications
A 3% Solution: Determination of the Hubble Constant with the Hubble Space Telescope and Wide Field Camera 3
Ferguson, Henry C.; Casertano, Stefano; Filippenko, Alexei V. +6 more
We use the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) to determine the Hubble constant from optical and infrared observations of over 600 Cepheid variables in the host galaxies of eight recent Type Ia supernovae (SNe Ia), providing the calibration for a magnitude-redshift relation based on 253 SNe Ia. Increased precision over p…
The Lesser Role of Starbursts in Star Formation at z = 2
Berta, S.; Magnelli, B.; Nordon, R. +31 more
Two main modes of star formation are know to control the growth of galaxies: a relatively steady one in disk-like galaxies, defining a tight star formation rate (SFR)-stellar mass sequence, and a starburst mode in outliers to such a sequence which is generally interpreted as driven by merging. Such starburst galaxies are rare but have much higher …
Galaxy Structure and Mode of Star Formation in the SFR-Mass Plane from z ~ 2.5 to z ~ 0.1
Barro, Guillermo; Hathi, Nimish P.; Kocevski, Dale D. +23 more
We analyze the dependence of galaxy structure (size and Sérsic index) and mode of star formation (ΣSFR and SFRIR/SFRUV) on the position of galaxies in the star formation rate (SFR) versus mass diagram. Our sample comprises roughly 640,000 galaxies at z ~ 0.1, 130,000 galaxies at z ~ 1, and 36,000 galaxies at z ~ 2.…
The Sins Survey of z ~ 2 Galaxy Kinematics: Properties of the Giant Star-forming Clumps
Lutz, D.; Förster Schreiber, N. M.; Genzel, R. +24 more
We have studied the properties of giant star-forming clumps in five z ~ 2 star-forming disks with deep SINFONI AO spectroscopy at the ESO VLT. The clumps reside in disk regions where the Toomre Q-parameter is below unity, consistent with their being bound and having formed from gravitational instability. Broad Hα/[N II] line wings demonstrate that…
Ultraviolet Luminosity Functions from 132 z ~ 7 and z ~ 8 Lyman-break Galaxies in the Ultra-deep HUDF09 and Wide-area Early Release Science WFC3/IR Observations
Trenti, M.; Oesch, P. A.; Carollo, C. M. +8 more
We identify 73 z ~ 7 and 59 z ~ 8 candidate galaxies in the reionization epoch, and use this large 26-29.4 AB mag sample of galaxies to derive very deep luminosity functions to < - 18 AB mag and the star formation rate (SFR) density at z ~ 7 and z ~ 8 (just 800 Myr and 650 Myr after recombination, respectively). The galaxy sample is derived usi…
A Photometric Redshift of z ~ 9.4 for GRB 090429B
Sakamoto, T.; D'Avanzo, P.; Greiner, J. +33 more
Gamma-ray bursts (GRBs) serve as powerful probes of the early universe, with their luminous afterglows revealing the locations and physical properties of star-forming galaxies at the highest redshifts, and potentially locating first-generation (Population III) stars. Since GRB afterglows have intrinsically very simple spectra, they allow robust re…
The NEWFIRM Medium-band Survey: Photometric Catalogs, Redshifts, and the Bimodal Color Distribution of Galaxies out to z ~ 3
van Dokkum, Pieter G.; Franx, Marijn; Illingworth, Garth D. +15 more
We present deep near-IR (NIR) medium-bandwidth photometry over the wavelength range 1-1.8 µm in the All-wavelength Extended Groth strip International Survey (AEGIS) and Cosmic Evolution Survey (COSMOS) fields. The observations were carried out using the NOAO Extremely Wide-Field Infrared Imager (NEWFIRM) on the Mayall 4 m Telescope on Kitt P…
The Major and Minor Galaxy Merger Rates at z < 1.5
Somerville, Rachel S.; Lotz, Jennifer M.; Primack, Joel R. +4 more
Calculating the galaxy merger rate requires both a census of galaxies identified as merger candidates and a cosmologically averaged "observability" timescale langT obs(z)rang for identifying galaxy mergers. While many have counted galaxy mergers using a variety of techniques, langT obs(z)rang for these techniques have been po…
On Star Formation Rates and Star Formation Histories of Galaxies Out to z ~ 3
Koekemoer, Anton M.; Maiolino, Roberto; Daddi, Emanuele +23 more
We compare multi-wavelength star formation rate (SFR) indicators out to z ~ 3 in the GOODS-South field. Our analysis uniquely combines U to 8 µm photometry from FIREWORKS, MIPS 24 µm and PACS 70, 100, and 160 µm photometry from the PEP, and Hα spectroscopy from the SINS survey. We describe a set of conversions that lead to a cont…
Disequilibrium Carbon, Oxygen, and Nitrogen Chemistry in the Atmospheres of HD 189733b and HD 209458b
Moses, Julianne I.; Fortney, J. J.; Showman, A. P. +8 more
We have developed a one-dimensional photochemical and thermochemical kinetics and diffusion model to study the effects of disequilibrium chemistry on the atmospheric composition of "hot-Jupiter" exoplanets. Here we investigate the coupled chemistry of neutral carbon, hydrogen, oxygen, and nitrogen species on HD 189733b and HD 209458b and we compar…