Search Publications
Connecting stellar mass and star-formation rate to dark matter halo mass out to z ∼ 2
Ivison, R. J.; Ilbert, O.; Béthermin, M. +17 more
We have constructed an extended halo model (EHM) which relates the total stellar mass and star-formation rate (SFR) to halo mass (Mh). An empirical relation between the distribution functions of total stellar mass of galaxies and host halo mass, tuned to match the spatial density of galaxies over 0 < z < 2 and the clustering prope…
A giant elliptical galaxy with a lightweight initial mass function
Lucey, John R.; Smith, Russell J.
We present new observations of the closest known strong-lensing galaxy, the σ ≈ 330 km s- 1 giant elliptical ESO325-G004, made with the ESO Very Large Telescope. The low redshift of the lens (zl = 0.035) results in arcs being formed at a small fraction of the effective radius (REin = 2.85 arcsec ≈ Reff/4…
The bright end of the exo-Zodi luminosity function: disc evolution and implications for exo-Earth detectability
Wyatt, M. C.; Kennedy, G. M.
We present the first characterisation of the 12 µm warm dust (`exo-Zodi') luminosity function around Sun-like stars, focusing on the dustiest systems that can be identified by the WISE mission. We use the sample of main-sequence stars observed by Hipparcos within 150 pc as an unbiased sample, and report the detection of six new warm dust can…
Formation of the compact jets in the black hole GX 339-4.
Aussel, H.; Tomsick, J. A.; Rodriguez, J. +15 more
Galactic black hole binaries produce powerful outflows which emit over almost the entire electromagnetic spectrum. Here, we report the first detection with the Herschel observatory of a variable far-infrared source associated with the compact jets of the black hole transient GX 339-4 during the decay of its recent 2010-2011 outburst, after the tra…
Properties of gas clumps and gas clumping factor in the intra-cluster medium
Simionescu, A.; Eckert, D.; Ettori, S. +2 more
The spatial distribution of gas matter inside galaxy clusters is not completely smooth, but may host gas clumps associated with substructures. These overdense gas substructures are generally a source of unresolved bias of X-ray observations towards high-density gas, but their bright luminosity peaks may be resolved sources within the intra cluster…
Extreme-velocity quasar outflows and the role of X-ray shielding
Chartas, G.; Charlton, J.; Hamann, F. +5 more
Quasar accretion disc winds observed via broad absorption lines (BALs) in the UV produce strong continuous absorption in X-rays. The X-ray absorber is believed to serve critically as a radiative shield to keep the outflow ionizations low enough for radiative driving. However, previous studies have shown that `mini-BAL' and narrow absorption line (…
HERMES: unveiling obscured star formation - the far-infrared luminosity function of ultraviolet-selected galaxies at z ∼ 1.5
Aussel, H.; Rodighiero, G.; Ivison, R. J. +22 more
We study the far-infrared and sub-millimetre properties of a sample of ultraviolet (UV) selected galaxies at z ∼ 1.5. Using stacking at 250, 350 and 500 µm from Herschel Space Observatory Spectral and Photometric Imaging Receiver (SPIRE) imaging of the Cosmological Evolution Survey (COSMOS) field obtained within the Herschel Multi-tiered Ext…
Challenges to our understanding of radio relics: X-ray observations of the Toothbrush cluster
Croston, J. H.; van Weeren, R. J.; Brüggen, M. +3 more
The cluster 1RXS J0603.3+4214 is a merging galaxy cluster that hosts three radio relics and a giant radio halo. The northern relic, the Toothbrush, is 1.9 Mpc long and has an unusual linear morphology. According to simple diffusive shock acceleration theory, its radio spectral index indicates a Mach number of 3.3-4.6. Here, we present results from…
Measurements and simulation of Faraday rotation across the Coma radio relic
Vazza, F.; Bonafede, A.; Govoni, F. +5 more
The aim of this work is to probe the magnetic field properties in relics and infall regions of galaxy clusters using Faraday rotation measures. We present Very Large Array multifrequency observations of seven sources in the region south-west of the Coma cluster, where the infalling group NGC 4839 and the relic 1253+275 are located. The Faraday rot…
Constraints on decreases in η Carinae's mass-loss from 3D hydrodynamic simulations of its binary colliding winds
Gull, T. R.; Corcoran, M. F.; Madura, T. I. +6 more
Recent work suggests that the mass-loss rate of the primary star ηA in the massive colliding wind binary η Carinae dropped by a factor of 2-3 between 1999 and 2010. We present results from large- (±1545 au) and small- (±155 au) domain, 3D smoothed particle hydrodynamics (SPH) simulations of η Car's colliding winds for three ηA