Search Publications
A Hubble Space Telescope lensing survey of X-ray luminous galaxy clusters - IV. Mass, structure and thermodynamics of cluster cores at z= 0.2
Smith, Graham P.; Smail, Ian; Kneib, Jean-Paul +3 more
We present a comprehensive space-based study of 10 X-ray luminous galaxy clusters (LX>= 8 × 1044 erg s-1, 0.1-2.4 keV) at z= 0.2. Hubble Space Telescope (HST) observations reveal numerous gravitationally lensed arcs for which we present four new spectroscopic redshifts, bringing the total to 13 confirmed arcs in…
What controls the CIV line profile in active galactic nuclei?
Laor, Ari; Baskin, Alexei
The high-ionization lines in active galactic nuclei (AGN), such as CIV, tend to be blueshifted with respect to the lower-ionization lines, such as Hβ, and often show a strong blue excess asymmetry not seen in the low-ionization lines. There is accumulating evidence that the Hβ profile is dominated by gravity, and thus provides a useful estimate of…
Multicomponent decompositions for a sample of S0 galaxies
Salo, Heikki; Laurikainen, Eija; Buta, Ronald
We have estimated the bulge-to-total (B/T) light ratios in the Ks band for a sample of 24 S0, S0/a and Sa galaxies by applying a two-dimensional multicomponent decomposition method. For the disc an exponential function is used, the bulges are fitted by a Sérsic R1/n function and the bars and ovals are described either by a Sé…
How large are the bars in barred galaxies?
Erwin, Peter
I present a study of the sizes (semimajor axes) of bars in disc galaxies, combining a detailed R-band study of 65 S0-Sb galaxies with the B-band measurements of 70 Sb-Sd galaxies from Martin (1995). As has been noted before with smaller samples, bars in early-type (S0-Sb) galaxies are clearly larger than bars in late-type (Sc-Sd) galaxies; this is…
The Hubble Deep Field North SCUBA Super-map - III. Optical and near-infrared properties of submillimetre galaxies
Dickinson, Mark; Mobasher, Bahram; Pope, Alexandra +3 more
We present a new submillimetre (submm) super-map in the Hubble Deep Field North (HDF-N) region (Great Observatories Origins Deep Survey North, GOODS-N, field), containing 40 statistically robust sources at 850µm. This map contains additional data, and several new sources, including one of the brightest blank-sky extragalactic submm sources e…
Transforming observational data and theoretical isochrones into the ACS/WFC Vega-mag system
Anderson, Jay; Salaris, Maurizio; Bedin, Luigi R. +5 more
We propose a zero-point photometric calibration of the data from the Advanced Camera for Surveys (ACS) Wide Field Channel (WFC) on board the Hubble Space Telescope, based on a spectrum of Vega and the most up-to-date in-flight transmission curves of the camera. This calibration is accurate at the level of a few hundredths of a magnitude. The main …
Spitzer imaging of i'-drop galaxies: old stars at z~ 6
Bunker, Andrew J.; Ellis, Richard S.; Stanway, Elizabeth R. +3 more
We present new evidence for mature stellar populations with ages >100Myr in massive galaxies (Mstellar > 1010Msolar) seen at a time when the Universe was less than 1Gyr old. We analyse the prominent detections of two z~ 6 star-forming galaxies (SBM03#1 and #3) made at wavelengths corresponding to the rest-fra…
Polar shapelets
Refregier, Alexandre; Massey, Richard
The shapelets method for image analysis is based upon the decomposition of localized objects into a series of orthogonal components with convenient mathematical properties. We extend the `Cartesian shapelet' formalism from earlier work, and construct `polar shapelet' basis functions that separate an image into components with explicit rotational s…
The progenitor of SN 2005cs in the Whirlpool Galaxy
Smartt, Stephen J.; Maund, Justyn R.; Danziger, I. John
The progenitor of SN 2005cs, in the galaxy M51, is identified in pre-explosion Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) Wide Field Channel (WFC) imaging. Differential astrometry, with post-explosion ACS High Resolution Channel (HRC) F555W images, permitted the identification of the progenitor with an accuracy of 0.006 arcsec.…
Near-infrared properties of i-drop galaxies in the Hubble Ultra Deep Field
Bunker, Andrew J.; McMahon, Richard G.; Stanway, Elizabeth R.
We analyse near-infrared Hubble Space Telescope (HST)/Near-Infrared Camera and Multi-Object Spectrometer F110W (J) and F160W (H) band photometry of a sample of 27 i'-drop candidate z~= 6 galaxies in the central region of the HST/Advanced Camera for Surveys Ultra Deep Field. The infrared colours of the 20 objects not affected by near neighbours are…