Search Publications
The ACS survey of Galactic globular clusters. XII. Photometric binaries along the main sequence
Moretti, A.; Anderson, J.; Milone, A. P. +15 more
Context. The fraction of binary stars is an important ingredient to interpret globular cluster dynamical evolution and their stellar population.
Aims: We investigate the properties of main-sequence binaries measured in a uniform photometric sample of 59 Galactic globular clusters that were observed by HST WFC/ACS as a part of the Globular Clu…
Can Minor Merging Account for the Size Growth of Quiescent Galaxies? New Results from the CANDELS Survey
Treu, Tommaso; Ellis, Richard S.; Newman, Andrew B. +1 more
The presence of extremely compact galaxies at z ~ 2 and their subsequent growth in physical size has been the cause of much puzzlement. We revisit the question using deep infrared Wide Field Camera 3 data to probe the rest-frame optical structure of 935 galaxies selected with 0.4 < z < 2.5 and stellar masses M * > 1010.7…
Supernova remnants: the X-ray perspective
Vink, Jacco
Supernova remnants are beautiful astronomical objects that are also of high scientific interest, because they provide insights into supernova explosion mechanisms, and because they are the likely sources of Galactic cosmic rays. X-ray observations are an important means to study these objects. And in particular the advances made in X-ray imaging s…
Spectroscopic Confirmation of Three z-dropout Galaxies at z = 6.844-7.213: Demographics of Lyα Emission in z ~ 7 Galaxies
Ono, Yoshiaki; Ouchi, Masami; Dickinson, Mark +10 more
We present the results of our ultra-deep Keck/DEIMOS spectroscopy of z-dropout galaxies in the Subaru Deep Field and Great Observatories Origins Deep Survey's northern field. For 3 out of 11 objects, we detect an emission line at ~1 µm with a signal-to-noise ratio of ~10. The lines show asymmetric profiles with high weighted skewness values,…
The Next Generation Virgo Cluster Survey (NGVS). I. Introduction to the Survey
Sawicki, Marcin; Jordán, Andrés; Wilson, Christine D. +49 more
The Next Generation Virgo Cluster Survey (NGVS) is a program that uses the 1 deg2 MegaCam instrument on the Canada-France-Hawaii Telescope to carry out a comprehensive optical imaging survey of the Virgo cluster, from its core to its virial radius—covering a total area of 104 deg2—in the u*griz bandpasses. Thanks to a dedicat…
Ubiquitous equatorial accretion disc winds in black hole soft states
Ponti, G.; Fender, R. P.; Neilsen, J. +3 more
High-resolution spectra of Galactic black holes (GBHs) reveal the presence of highly ionized absorbers. In one GBH, accreting close to the Eddington limit for more than a decade, a powerful accretion disc wind is observed to be present in softer X-ray states and it has been suggested that it can carry away enough mass and energy to quench the radi…
CANDELS: Constraining the AGN-Merger Connection with Host Morphologies at z ~ 2
Bell, Eric F.; Giavalisco, Mauro; Grogin, Norman A. +35 more
Using Hubble Space Telescope/WFC3 imaging taken as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, we examine the role that major galaxy mergers play in triggering active galactic nucleus (AGN) activity at z ~ 2. Our sample consists of 72 moderate-luminosity (L X ~ 1042-44 erg s-1) AGNs …
The Panchromatic Hubble Andromeda Treasury
Bell, Eric F.; Skillman, Evan D.; Williams, Benjamin F. +30 more
The Panchromatic Hubble Andromeda Treasury is an ongoing Hubble Space Telescope Multi-Cycle Treasury program to image ~1/3 of M31's star-forming disk in six filters, spanning from the ultraviolet (UV) to the near-infrared (NIR). We use the Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) to resolve the galaxy into millions of indiv…
A Catalog of 132,684 Clusters of Galaxies Identified from Sloan Digital Sky Survey III
Han, J. L.; Wen, Z. L.; Liu, F. S.
Using the photometric redshifts of galaxies from the Sloan Digital Sky Survey III (SDSS-III), we identify 132,684 clusters in the redshift range of 0.05 <= z < 0.8. Monte Carlo simulations show that the false detection rate is less than 6% for the whole sample. The completeness is more than 95% for clusters with a mass of M 200 &g…
Gravitational detection of a low-mass dark satellite galaxy at cosmological distance
Vegetti, S.; McKean, J. P.; Auger, M. W. +3 more
The mass function of dwarf satellite galaxies that are observed around Local Group galaxies differs substantially from simulations based on cold dark matter: the simulations predict many more dwarf galaxies than are seen. The Local Group, however, may be anomalous in this regard. A massive dark satellite in an early-type lens galaxy at a redshift …