Search Publications
Evidence for a radiatively driven disc-wind in PDS 456?
Tombesi, F.; Reeves, J. N.; Braito, V. +5 more
We present a newly discovered correlation between the wind outflow velocity and the X-ray luminosity in the luminous (Lbol ∼ 1047erg s - 1) nearby (z = 0.184) quasar PDS 456. All the contemporary XMM-Newton, NuSTAR and Suzaku observations from 2001-2014 were revisited and we find that the centroid energy of the blu…
Extreme jet ejections from the black hole X-ray binary V404 Cygni
Gurwell, M.; Russell, D. M.; Fender, R. +14 more
We present simultaneous radio through sub-mm observations of the black hole X-ray binary (BHXB) V404 Cygni during the most active phase of its June 2015 outburst. Our 4 h long set of overlapping observations with the Very Large Array, the Sub-millimeter Array and the James Clerk Maxwell Telescope (SCUBA-2) covers eight different frequency bands (i…
Luminosity dependence of the cyclotron line and evidence for the accretion regime transition in V 0332+53
Doroshenko, Victor; Tsygankov, Sergey S.; Mushtukov, Alexander A. +4 more
We report on the analysis of NuSTAR observations of the Be-transient X-ray pulsar V 0332+53 during the giant outburst in 2015 and another minor outburst in 2016. We confirm the cyclotron-line energy-luminosity correlation previously reported in the source and the line energy decrease during the giant outburst. Based on 2016 observations, we find t…
Using dust, gas and stellar mass-selected samples to probe dust sources and sinks in low-metallicity galaxies
Baes, M.; Dunne, L.; Maddox, S. +8 more
We combine samples of nearby galaxies with Herschel photometry selected on their dust, metal, H I and stellar mass content, and compare these to chemical evolution models in order to discriminate between different dust sources. In a companion paper, we used an H I-selected sample of nearby galaxies to reveal a subsample of very gas-rich (gas fract…
The slight spin of the old stellar halo
Gómez, Facundo A.; Marinacci, Federico; Pakmor, Rüdiger +4 more
We combine Gaia data release 1 astrometry with Sloan Digital Sky Survey (SDSS) images taken some ∼10-15 years earlier, to measure proper motions of stars in the halo of our Galaxy. The SDSS-Gaia proper motions have typical statistical errors of 2 mas yr-1 down to r ∼ 20 mag, and are robust to variations with magnitude and colour. Armed …
Hunting black holes with Gaia
Loeb, Abraham; Mashian, Natalie
We predict the number of black holes with stellar companions that are potentially detectable with Gaia astrometry over the course of its 5-yr mission. Our model estimates that nearly 2 × 105 astrometric binaries hosting black holes and stellar companions brighter than Gaia's detection threshold, G ∼ 20, should be discovered with 5σ sens…
Spectroscopic properties of luminous Ly α emitters at z ≈ 6-7 and comparison to the Lyman-break population
Sobral, David; Mobasher, Bahram; Darvish, Behnam +5 more
We present spectroscopic follow-up of candidate luminous Ly α emitters (LAEs) at z = 5.7-6.6 in the SA22 field with VLT/X-SHOOTER. We confirm two new luminous LAEs at z = 5.676 (SR6) and z = 6.532 (VR7), and also present HST follow-up of both sources. These sources have luminosities LLy α ≈ 3 × 1043 erg s-1, very h…
Massive post-starburst galaxies at z > 1 are compact proto-spheroids
Simpson, Chris; Wild, Vivienne; Almaini, Omar +6 more
We investigate the relationship between the quenching of star formation and the structural transformation of massive galaxies, using a large sample of photometrically selected post-starburst galaxies in the UKIDSS Ultra-Deep Survey field. We find that post-starburst galaxies at high redshift (z > 1) show high Sérsic indices, significantly highe…
WISDOM Project - II. Molecular gas measurement of the supermassive black hole mass in NGC 4697
Sarzi, Marc; Cappellari, Michele; Davis, Timothy A. +3 more
As part of the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM) project, we present an estimate of the mass of the supermassive black hole (SMBH) in the nearby fast-rotating early-type galaxy NGC 4697. This estimate is based on Atacama Large Millimeter/submillimeter Array (ALMA) cycle-3 observations of the 12CO(2-1) emissio…
The evolving far-IR galaxy luminosity function and dust-obscured star formation rate density out to z≃5.
Scott, D.; McLure, R. J.; Dunlop, J. S. +5 more
We present a new measurement of the evolving galaxy far-IR luminosity function (LF) extending out to redshifts z ≃ 5, with resulting implications for the level of dust-obscured star formation density in the young Universe. To achieve this, we have exploited recent advances in sub-mm/mm imaging with SCUBA-2 on the James Clerk Maxwell Telescope and …