Search Publications
Improved Cosmological Constraints from New, Old, and Combined Supernova Data Sets
Perdereau, O.; Frye, B. L.; Suntzeff, N. B. +67 more
We present a new compilation of Type Ia supernovae (SNe Ia), a new data set of low-redshift nearby-Hubble-flow SNe, and new analysis procedures to work with these heterogeneous compilations. This "Union" compilation of 414 SNe Ia, which reduces to 307 SNe after selection cuts, includes the recent large samples of SNe Ia from the Supernova Legacy S…
Evolution of asymptotic giant branch stars. II. Optical to far-infrared isochrones with improved TP-AGB models
Bressan, A.; Girardi, L.; Granato, G. L. +3 more
We present a large set of theoretical isochrones, whose distinctive features mostly reside on the greatly-improved treatment of the thermally-pulsing asymptotic giant branch (TP-AGB) phase. Essentially, we have coupled the TP-AGB tracks described in Paper I, at their stages of pre-flash quiescent H-shell burning, with the evolutionary tracks for t…
A Cosmological Framework for the Co-Evolution of Quasars, Supermassive Black Holes, and Elliptical Galaxies. I. Galaxy Mergers and Quasar Activity
Hernquist, Lars; Cox, Thomas J.; Hopkins, Philip F. +1 more
We develop a model for the cosmological role of mergers in the evolution of starbursts, quasars, and spheroidal galaxies. By combining theoretically well-constrained halo and subhalo mass functions as a function of redshift and environment with empirical halo occupation models, we can estimate where galaxies of given properties live at a particula…
Constraints on the Self-Interaction Cross Section of Dark Matter from Numerical Simulations of the Merging Galaxy Cluster 1E 0657-56
Gonzalez, Anthony H.; Markevitch, Maxim; Clowe, Douglas +2 more
We compare recent results from X-ray, strong lensing, weak lensing, and optical observations with numerical simulations of the merging galaxy cluster 1E 0657-56. X-ray observations reveal a bullet-like subcluster with a prominent bow shock, which gives an estimate for the merger velocity of 4700 km s-1, while lensing results show that t…
Optical Images of an Exosolar Planet 25 Light-Years from Earth
Kalas, Paul; Fitzgerald, Michael P.; Graham, James R. +6 more
Fomalhaut, a bright star 7.7 parsecs (25 light-years) from Earth, harbors a belt of cold dust with a structure consistent with gravitational sculpting by an orbiting planet. Here, we present optical observations of an exoplanet candidate, Fomalhaut b. Fomalhaut b lies about 119 astronomical units (AU) from the star and 18 AU of the dust belt, matc…
Confirmation of the Remarkable Compactness of Massive Quiescent Galaxies at z ~ 2.3: Early-Type Galaxies Did not Form in a Simple Monolithic Collapse
van Dokkum, Pieter G.; Franx, Marijn; Illingworth, Garth D. +9 more
Using deep near-infrared spectroscopy, Kriek et al. found that ~45% of massive galaxies at z ~ 2.3 have evolved stellar populations and little or no ongoing star formation. Here we determine the sizes of these quiescent galaxies using deep, high-resolution images obtained with HST/NIC2 and laser guide star (LGS)-assisted Keck/adaptive optics (AO).…
Submillimeter Galaxies at z ~ 2: Evidence for Major Mergers and Constraints on Lifetimes, IMF, and CO-H2 Conversion Factor
Smail, I.; Lutz, D.; Cimatti, A. +17 more
We report subarcsecond resolution IRAM PdBI millimeter CO interferometry of four z ~ 2 submillimeter galaxies (SMGs), and sensitive CO(3-2) flux limits toward three z ~ 2 UV/optically selected star-forming galaxies. The new data reveal for the first time spatially resolved CO gas kinematics in the observed SMGs. Two of the SMGs show double or mult…
From Rings to Bulges: Evidence for Rapid Secular Galaxy Evolution at z ~ 2 from Integral Field Spectroscopy in the SINS Survey
Lutz, D.; Cimatti, A.; Daddi, E. +22 more
We present Hα integral field spectroscopy of well-resolved, UV/optically selected z ~ 2 star-forming galaxies as part of the SINS survey with SINFONI on the ESO VLT. Our laser guide star adaptive optics and good seeing data show the presence of turbulent rotating star-forming outer rings/disks, plus central bulge/inner disk components, whose mass …
The Stellar Mass Assembly of Galaxies from z = 0 to z = 4: Analysis of a Sample Selected in the Rest-Frame Near-Infrared with Spitzer
Barro, Guillermo; Pérez-González, Pablo G.; Rieke, George H. +8 more
Using a sample of ~28,000 sources selected at 3.6-4.5 µm with Spitzer observations of the Hubble Deep Field North, the Chandra Deep Field South, and the Lockman Hole (surveyed area ~664 arcmin2), we study the evolution of the stellar mass content of the universe at 0 < z < 4. We calculate stellar masses and photometric redsh…
GMASS ultradeep spectroscopy of galaxies at z ~ 2. II. Superdense passive galaxies: how did they form and evolve?
Berta, S.; Cimatti, A.; Daddi, E. +13 more
Aims: The aim of this work is to investigate the physical, structural and evolutionary properties of old, passive galaxies at z > 1.4 and to place new constraints on massive galaxy formation and evolution.
Methods: We combine ultradeep optical spectroscopy from the GMASS project (Galaxy Mass Assembly ultradeep Spectroscopic Survey) with GOO…