Search Publications
Stellar Diameters and Temperatures. II. Main-sequence K- and M-stars
López-Morales, Mercedes; Muirhead, Philip S.; Kane, Stephen R. +21 more
We present interferometric angular diameter measurements of 21 low-mass, K- and M-dwarfs made with the CHARA Array. This sample is enhanced by adding a collection of radius measurements published in the literature to form a total data set of 33 K-M-dwarfs with diameters measured to better than 5%. We use these data in combination with the Hipparco…
The Hawaii Infrared Parallax Program. I. Ultracool Binaries and the L/T Transition
Dupuy, Trent J.; Liu, Michael C.
We present the first results from our high-precision infrared (IR) astrometry program at the Canada-France-Hawaii Telescope. We measure parallaxes for 83 ultracool dwarfs (spectral types M6-T9) in 49 systems, with a median uncertainty of 1.1 mas (2.3%) and as good as 0.7 mas (0.8%). We provide the first parallaxes for 48 objects in 29 systems, and…
New Constraints on the Evolution of the Stellar-to-dark Matter Connection: A Combined Analysis of Galaxy-Galaxy Lensing, Clustering, and Stellar Mass Functions from z = 0.2 to z =1
Koekemoer, Anton M.; Schrabback, Tim; Leauthaud, Alexie +20 more
Using data from the COSMOS survey, we perform the first joint analysis of galaxy-galaxy weak lensing, galaxy spatial clustering, and galaxy number densities. Carefully accounting for sample variance and for scatter between stellar and halo mass, we model all three observables simultaneously using a novel and self-consistent theoretical framework. …
A Revised Age for Upper Scorpius and the Star Formation History among the F-type Members of the Scorpius-Centaurus OB Association
Mamajek, Eric E.; Pecaut, Mark J.; Bubar, Eric J.
We present an analysis of the ages and star formation history of the F-type stars in the Upper Scorpius (US), Upper Centaurus-Lupus (UCL), and Lower Centaurus-Crux (LCC) subgroups of Scorpius-Centaurus (Sco-Cen), the nearest OB association. Our parent sample is the kinematically selected Hipparcos sample of de Zeeuw et al., restricted to the 138 F…
Scaling relations for galaxy clusters in the Millennium-XXL simulation
White, S. D. M.; Baugh, C. M.; Frenk, C. S. +3 more
We present a very large high-resolution cosmological N-body simulation, the Millennium-XXL or MXXL, which uses 303 billion particles to represent the formation of dark matter structures throughout a 4.1 Gpc box in a Λ cold dark matter cosmology. We create sky maps and identify large samples of galaxy clusters using surrogates for four different ob…
Structural Parameters of Galaxies in CANDELS
Kartaltepe, J. S.; Barden, M.; Ferguson, H. C. +19 more
We present global structural parameter measurements of 109,533 unique, H F160W-selected objects from the CANDELS multi-cycle treasury program. Sérsic model fits for these objects are produced with GALFIT in all available near-infrared filters (H F160W, J F125W and, for a subset, Y F105W). The parameters …
The Evolving Interstellar Medium of Star-forming Galaxies since z = 2 as Probed by Their Infrared Spectral Energy Distributions
Daddi, E.; Elbaz, D.; Béthermin, M. +11 more
Using data from the mid-infrared to millimeter wavelengths for individual galaxies and for stacked ensembles at 0.5 < z < 2, we derive robust estimates of dust masses (M dust) for main-sequence (MS) galaxies, which obey a tight correlation between star formation rate (SFR) and stellar mass (M *), and for starbursting ga…
UV-continuum Slopes at z ~ 4-7 from the HUDF09+ERS+CANDELS Observations: Discovery of a Well-defined UV Color-Magnitude Relationship for z >= 4 Star-forming Galaxies
Trenti, M.; Oesch, P. A.; Carollo, C. M. +8 more
Ultra-deep Advanced Camera for Surveys (ACS) and WFC3/IR HUDF+HUDF09 data, along with the wide-area GOODS+ERS+CANDELS data over the CDF-S GOODS field, are used to measure UV colors, expressed as the UV-continuum slope β, of star-forming galaxies over a wide range of luminosity (0.1L* z = 3 to 2L* z = 3) at high redshift (z ~ …
Semi-analytic modelling of the extragalactic background light and consequences for extragalactic gamma-ray spectra
Somerville, Rachel S.; Primack, Joel R.; Domínguez, Alberto +1 more
Attenuation of high-energy gamma-rays by pair production with ultraviolet, optical and infrared (IR) extragalactic background light (EBL) photons provides a link between the history of galaxy formation and high-energy astrophysics. We present results from our latest semi-analytic models (SAMs), which employ the main ingredients thought to be impor…
Present-day cosmic abundances. A comprehensive study of nearby early B-type stars and implications for stellar and Galactic evolution and interstellar dust models
Przybilla, N.; Nieva, M. -F.
Context. Early B-type stars are ideal indicators for present-day cosmic abundances since they preserve their pristine abundances and typically do not migrate far beyond their birth environments over their short lifetimes, in contrast to older stars like the Sun. They are also unaffected by depletion onto dust grains, unlike the cold/warm interstel…