Search Publications
Quasars, their host galaxies and their central black holes
McLure, R. J.; Dunlop, J. S.; Hughes, D. H. +3 more
We present the final results from our deep Hubble Space Telescope (HST) imaging study of the host galaxies of radio-quiet quasars (RQQs), radio-loud quasars (RLQs) and radio galaxies (RGs). We describe and analyse new Wide Field & Planetary Camera 2 (WFPC2) R-band observations for 14 objects, which when combined with the first tranche of HST i…
The Cosmic Lens All-Sky Survey - II. Gravitational lens candidate selection and follow-up
Pearson, T. J.; McKean, J. P.; Blandford, R. D. +19 more
We report the final results of the search for gravitationally lensed flat-spectrum radio sources found in the combination of CLASS (Cosmic Lens All-Sky Survey) and JVAS (Jodrell Bank VLA Astrometric Survey). VLA (Very Large Array) observations of 16503 sources have been made, resulting in the largest sample of arcsec-scale lens systems available. …
Shapelets - I. A method for image analysis
Refregier, Alexandre
We present a new method for the analysis of images, a fundamental task in observational astronomy. It is based on the linear decomposition of each object in the image into a series of localized basis functions of different shapes, which we call `shapelets'. A particularly useful set of complete and orthonormal shapelets is that consisting of weigh…
Surface brightness profiles and structural parameters for 53 rich stellar clusters in the Large Magellanic Cloud
Mackey, A. D.; Gilmore, G. F.
We have compiled a pseudo-snapshot data set of two-colour observations from the Hubble Space Telescope archive for a sample of 53 rich LMC clusters with ages of 106-1010 yr. We present surface brightness profiles for the entire sample, and derive structural parameters for each cluster, including core radii, and luminosity and…
Star cluster formation and disruption time-scales - I. An empirical determination of the disruption time of star clusters in four galaxies
Lamers, H. J. G. L. M.; Boutloukos, S. G.
We have derived the disruption times of star clusters from cluster samples of four galaxies, M51, M33, the Small Magellanic Cloud (SMC) and the solar neighbourhood. If the disruption time of clusters in a galaxy depends only on their initial mass as tdis(yr) =t4dis(Mcl/104 Msolar)
Lyman break galaxies and the star formation rate of the Universe at z~ 6
Bunker, Andrew J.; McMahon, Richard G.; Stanway, Elizabeth R.
We determine the space density of UV-luminous starburst galaxies at z~ 6 using deep HST ACS SDSS-i' (F775W) and SDSS-z' (F850LP) and VLT ISAAC J and Ks band imaging of the Chandra Deep Field South. We find eight galaxies and one star with (i'-z') > 1.5 to a depth of z'AB= 25.6 (an 8σ detection in each of the 3 available AC…
Star cluster formation and evolution in nearby starburst galaxies - II. Initial conditions
Bastian, N.; de Grijs, R.; Anders, P. +3 more
We use the ages, masses and metallicities of the rich young star cluster systems in the nearby starburst galaxies NGC 3310 and 6745 to derive their cluster formation histories and subsequent evolution. We further expand our analysis of the systematic uncertainties involved in the use of broad-band observations to derive these parameters (Paper I) …
A pulsational approach to near-infrared and visual magnitudes of RR Lyr stars
Degl'Innocenti, S.; Marconi, M.; Bono, G. +3 more
In this paper, we present an improved theoretical scenario concerning near-infrared and visual magnitudes of RR Lyr variables, as based on up-to-date pulsating models. New relations connecting V and K absolute magnitudes with periods, mass, luminosity and metal content are discussed separately for fundamental and first-overtone pulsators. We also …
Kinematically quiet haloes around z~ 2.5 radio galaxies. Keck spectroscopy
Pentericci, L.; Humphrey, A.; Villar-Martín, M. +3 more
We present the results of the kinematic study of the extended gas in a sample of 10 high-redshift radio galaxies (z~ 2.5) based on high signal-to-noise ratio Keck II and Very Large Telescope (VLT) long-slit spectroscopy. In addition to the typical high surface brightness kinematically perturbed regions (FWHM and velocity shifts >1000 km s-…
The remarkable rapid X-ray, ultraviolet, optical and infrared variability in the black hole XTE J1118+480
Chaty, S.; Cui, W.; Horne, Keith +6 more
The transient black-hole binary XTE J1118+480 exhibited dramatic rapid variability at all wavelengths which were suitably observed during its 2000 April-July outburst. We examine time-resolved X-ray, ultraviolet, optical and infrared data spanning the plateau phase of the outburst. We find that both X-ray and infrared bands show large amplitude va…