Search Publications
Comprehensive study of a z = 2.35 DLA Galaxy: mass, metallicity, age, morphology and SFR from HST and VLT
Pettini, Max; Noterdaeme, Pasquier; Gallazzi, Anna +8 more
We present a detailed study of the emission from a z = 2.35 galaxy that causes damped Lyman α absorption in the spectrum of the background quasar (QSO), SDSS J2222-0946. We present the results of extensive analyses of the stellar continuum covering the rest frame optical-UV regime based on broad-band Hubble Space Telescope (HST) imaging, and of sp…
Evidence for a correlation between the sizes of quiescent galaxies and local environment to z ∼ 2
Grogin, Norman A.; Kocevski, Dale D.; Koekemoer, Anton M. +14 more
We present evidence for a strong relationship between galaxy size and environment for the quiescent population in the redshift range 1 < z < 2. Environments were measured using projected galaxy overdensities on a scale of 400 kpc, as determined from ∼96 000 K-band-selected galaxies from the UKIDSS Ultra Deep Survey (UDS). Sizes were determin…
Revealing the X-ray source in IRAS 13224-3809 through flux-dependent reverberation lags
Fabian, A. C.; Miniutti, G.; Uttley, P. +2 more
IRAS 13224-3809 was observed in 2011 for 500 ks with the XMM-Newton observatory. We detect highly significant X-ray lags between soft (0.3-1 keV) and hard (1.2-5 keV) energies. The hard band lags the soft at low frequencies (i.e. hard lag), while the opposite (i.e. soft lag) is observed at high frequencies. In this paper, we study the lag during f…
Constraints on dark energy with the LOSS SN Ia sample
Filippenko, Alexei V.; Li, Weidong; Ganeshalingam, Mohan
We present a cosmological analysis of the Lick Observatory Supernova Search (LOSS) Type Ia supernova (SN Ia) photometry sample introduced by Ganeshalingam et al. These supernovae (SNe) provide an effective anchor point to estimate cosmological parameters when combined with data sets at higher redshift. The data presented by Ganeshalingam et al. ha…
The polarized gamma-ray burst GRB 061122
Covino, S.; Götz, D.; Bošnjak, Ž. +2 more
We report on the polarization measure, obtained with IBIS on board INTEGRAL, of the prompt emission of GRB 061122. Over an 8 s interval containing the brightest part of the gamma-ray burst (GRB) we put a lower limit on its polarization fraction of 60 per cent at 68 per cent confidence level (c.l.) and of 33 per cent at 90 per cent c.l. on the 250-…
Population of persistent high-mass X-ray binaries in the Milky Way
Tsygankov, S. S.; Lutovinov, A. A.; Revnivtsev, M. G. +1 more
We present results of the study of persistent high-mass X-ray binaries (HMXBs) in the Milky Way, obtained from the deep INTEGRAL Galactic plane survey. This survey provides us a new insight into the population of HMXBs because almost half of the whole sample consists of sources discovered with INTEGRAL. It is demonstrated for the first time that t…
A low-mass cut-off near the hydrogen burning limit for Salpeter-like initial mass functions in early-type galaxies
Treu, Tommaso; Czoske, Oliver; Koopmans, Léon V. E. +3 more
We conduct a detailed investigation of the properties of the stellar initial mass function (IMF) in two massive early-type lens galaxies with velocity dispersions of σ ≃ 245 and 325 km s-1, for which both Hubble Space Telescope imaging and X-Shooter spectra are available. We compare the inferences obtained from two fully independent met…
Molecular gas in the centre of nearby galaxies from VLT/SINFONI integral field spectroscopy - I. Morphology and mass inventory
Saglia, R. P.; Nowak, N.; Thomas, J. +7 more
We present the first results of an analysis of the properties of the molecular gas in the nuclear regions (r ≲ 300 pc) of a sample of six nearby galaxies, based on new high-spatial-resolution observations obtained in the K-band with the near-infrared integral field spectrograph SINFONI at the Very Large Telescope. We derive 2D distributions of the…
Galaxy Zoo: bulgeless galaxies with growing black holes
Moran, Edward C.; Schawinski, Kevin; Kaviraj, Sugata +8 more
The growth of supermassive black holes appears to be driven by galaxy mergers, violent merger-free processes and/or `secular' processes. In order to quantify the effects of secular evolution on black hole growth, we study a sample of active galactic nuclei (AGN) in galaxies with a calm formation history free of significant mergers, a population th…
X-ray exploration of the outskirts of the nearby Centaurus cluster using Suzaku and Chandra
Simionescu, A.; Fabian, A. C.; Sanders, J. S. +2 more
We present Suzaku observations of the Centaurus cluster out to 0.95r200, taken along a strip to the north-west. We have also used congruent Chandra observations of the outskirts to resolve point sources down to a threshold flux around seven times lower than that achievable with just Suzaku data, considerably reducing the systematic unce…