Search Publications
Probing the role of the galactic environment in the formation of stellar clusters, using M83 as a test bench
Bastian, N.; Adamo, A.; Silva-Villa, E. +2 more
We present a study of the M83 cluster population, covering the disc of the galaxy between radii of 0.45 and 4.5 kpc. We aim to probe the properties of the cluster population as a function of distance from the galactic centre. We observe a net decline in cluster formation efficiency (Γ, i.e. amount of star formation happening in bound clusters) fro…
A remarkably flat relationship between the average star formation rate and AGN luminosity for distant X-ray AGN
Alexander, D. M.; Swinbank, A. M.; Del Moro, A. +5 more
In this study, we investigate the relationship between the star formation rate (SFR) and AGN luminosity (L_AGN) for ∼2000 X-ray detected AGN. The AGN span over three orders of magnitude in X-ray luminosity (10^{42} < L_{2-8 keV} < 10^{45.5} erg s^{-1}) and are in the redshift range z = 0.2-2.5. Using infrared (IR) photometry (8-500 µ m…
Cosmic discordance: are Planck CMB and CFHTLenS weak lensing measurements out of tune?
Jain, Bhuvnesh; Zuntz, Joe; Bridle, Sarah +2 more
We examine the level of agreement between low-redshift weak lensing data and the cosmic microwave background using measurements from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) and Planck+Wilkinson Microwave Anisotropy Probe (WMAP) polarization. We perform an independent analysis of the CFHTLenS six bin tomography results of Heyma…
New redshift z ≃ 9 galaxies in the Hubble Frontier Fields: implications for early evolution of the UV luminosity density
McLure, R. J.; Dunlop, J. S.; McLeod, D. J. +3 more
We present the results of a new search for galaxies at redshift z ≃ 9 in the first two Hubble Frontier Fields with completed HST WFC3/IR and ACS imaging. To ensure robust photometric redshift solutions, and to minimize incompleteness, we confine our search to objects with H160 < 28.6 (AB mag), consider only image regions with an rms …
Photohadronic origin of γ -ray BL Lac emission: implications for IceCube neutrinos
Padovani, P.; Resconi, E.; Mastichiadis, A. +2 more
The recent IceCube discovery of 0.1-1 PeV neutrinos of astrophysical origin opens up a new era for high-energy astrophysics. Although there are various astrophysical candidate sources, a firm association of the detected neutrinos with one (or more) of them is still lacking. A recent analysis of plausible astrophysical counterparts within the error…
The behaviour of dark matter associated with four bright cluster galaxies in the 10 kpc core of Abell 3827
Richard, Johan; Hilton, Matt; Massey, Richard +20 more
Galaxy cluster Abell 3827 hosts the stellar remnants of four almost equally bright elliptical galaxies within a core of radius 10 kpc. Such corrugation of the stellar distribution is very rare, and suggests recent formation by several simultaneous mergers. We map the distribution of associated dark matter, using new Hubble Space Telescope imaging …
X-shooter reveals powerful outflows in z ∼ 1.5 X-ray selected obscured quasi-stellar objects
Lutz, D.; Maiolino, R.; Salvato, M. +20 more
We present X-shooter at Very Large Telescope observations of a sample of 10 luminous, X-ray obscured quasi-stellar objects (QSOs) at z ∼ 1.5 from the XMM-COSMOS survey, expected to be caught in the transitioning phase from starburst to active galactic nucleus (AGN)-dominated systems. The main selection criterion is X-ray detection at bright fluxes…
The search for failed supernovae with the Large Binocular Telescope: first candidates
Kochanek, C. S.; Stanek, K. Z.; Gerke, J. R.
We are monitoring 27 galaxies within 10 Mpc using the Large Binocular Telescope to search for failed supernovae (SNe), massive stars that collapse to form a black hole without an SN explosion. We present the results from the first 4 yr of survey data, during which these galaxies were observed to produce three successful core-collapse SNe. We searc…
GREAT3 results - I. Systematic errors in shear estimation and the impact of real galaxy morphology
Zhang, Jun; Hogg, David W.; Gavazzi, Raphaël +40 more
We present first results from the third GRavitational lEnsing Accuracy Testing (GREAT3) challenge, the third in a sequence of challenges for testing methods of inferring weak gravitational lensing shear distortions from simulated galaxy images. GREAT3 was divided into experiments to test three specific questions, and included simulated space- and …
On the possible environmental effect in distributing heavy elements beyond individual gaseous haloes
Johnson, Sean D.; Chen, Hsiao-Wen; Mulchaey, John S.
We present a study of extended galaxy halo gas through H I and O VI absorption over two decades in projected distance at z ≈ 0.2. The study is based on a sample of 95 galaxies from a highly complete (>80 per cent) survey of faint galaxies (L > 0.1L*) with archival quasar absorption spectra and 53 galaxies from the literature. A cl…