Search Publications
Density-potential pairs for spherical stellar systems with Sérsic light profiles and (optional) power-law cores
Graham, Alister W.; Terzić, Balša
Popular models for describing the luminosity-density profiles of dynamically hot stellar systems (e.g. Jaffe, Hernquist, Dehnen) were constructed with the desire to match the deprojected form of an R1/4 light profile. Real galaxies, however, are now known to have a range of different light-profile shapes that scale with mass. Consequent…
Ly-α and ultraviolet emission from high-redshift gamma-ray burst hosts: to what extent do gamma-ray bursts trace star formation?
Östlin, G.; Jóhannesson, G.; Watson, D. +9 more
We report the result of a search for Lyα emission from the host galaxies of the gamma-ray bursts (GRBs) 030226 (z= 1.986), 021004 (z= 2.335) and 020124 (z= 3.198). We find that the host galaxy of GRB 021004 is an extended (around 8 kpc) strong Lyα emitter with a rest-frame equivalent width (EW) of 68+12-11Å, and a star format…
The nature of the molecular gas system in the core of NGC 1275
Edge, A. C.; Johnstone, R. M.; Wilman, R. J.
We present near-infrared integral field spectroscopy of the central kiloparsec of NGC 1275 at the heart of the Perseus cluster of galaxies, obtained with the Integral Field Unit (IFU) of the United Kingdom Infrared Telescope (UKIRT) Imaging Spectrometer (UIST). The nuclear ro-vibrational H2 emission is spatially resolved and is likely t…
A submillimetre survey of Lyman α haloes in the SA22 protocluster at z= 3.1
Ivison, R. J.; Taniguchi, Y.; Smail, Ian +7 more
We present the results from a submillimetre (submm) survey of a sample of 23 giant Lyman α (Lyα) emitting nebulae in the overdensity at z= 3.09 in the SA22 field. These objects, which have become known as Lyα Blobs (LABs), have a diverse range of morphology and surface brightness, but the nature of their power source remains unclear, with both coo…
The star-forming environment of an ultraluminous X-ray source in NGC4559: an optical study
Cropper, Mark; Soria, Roberto; Wu, Kinwah +2 more
We have studied the candidate optical counterparts and the stellar population in the star-forming complex around the bright ultraluminous X-ray source (ULX) in the western part of the spiral galaxy NGC4559, using the HST Wide Field Planetary Camera 2 (WFPC2), XMM-Newton/Optical Monitor and ground-based data. We find that the ULX is located near a …
Hubble Space Telescope imaging of the progenitor sites of six nearby core-collapse supernovae
Smartt, S. J.; Maund, J. R.
The search for the progenitors of six core-collapse supernovae (CCSNe) in archival Hubble Space Telescope (HST) WFPC2 pre-explosion imaging is presented. These SNe are 1999an, 1999br, 1999ev, 2000ds, 2000ew and 2001B. Post-explosion imaging of the SNe, with the HST ACS/WFC, has been utilized with the technique of differential astrometry to identif…
Regularized orbit models unveiling the stellar structure and dark matter halo of the Coma elliptical NGC 4807
Saglia, R. P.; Thomas, D.; Thomas, J. +5 more
This is the second in a series of papers dedicated to unveiling the mass structure and orbital content of a sample of flattened early-type galaxies in the Coma cluster. The ability of our orbit libraries to reconstruct internal stellar motions and the mass composition of a typical elliptical in the sample is investigated by means of Monte Carlo si…
A photoionization-modelling study of 30 Doradus: the case for small-scale chemical inhomogeneity
Tsamis, Yiannis G.; Péquignot, Daniel
Photoionization models of the giant HII region (GHIIR) 30 Doradus are built and confronted to available ultraviolet (UV), optical, infrared (IR) [Infrared Space Observatory (ISO)] and radio spectra, under blackbody or CoStar spectral energy distributions for the primary source and various density distributions for the nebular gas. Chemically homog…
Constraints on the ionizing flux emitted by T Tauri stars
Clarke, C. J.; Pringle, J. E.; Alexander, R. D.
We present the results of an analysis of ultraviolet observations of T Tauri stars (TTs). By analysing emission measures taken from the literature, we derive rates of ionizing photons from the chromospheres of five classical TTs in the range ~1041-1044 photon s-1, although these values are subject to large uncertai…
A Chandra X-ray survey of nearby dwarf starburst galaxies - II. Starburst properties and outflows
Ott, Jürgen; Walter, Fabian; Brinks, Elias
We present a comprehensive comparison of the X-ray properties of a sample of eight dwarf starburst galaxies observed with Chandra (IZw18, VIIZw403, NGC1569, NGC3077, NGC4214, NGC4449, NGC5253 and He2-10). In PaperI, we presented in detail the data reduction and analysis of the individual galaxies. For the unresolved X-ray sources, we find the foll…