Search Publications
The dark halo of the main lens galaxy in QSO 0957 + 561
Gil-Merino, R.; Goicoechea, L. J.; Ullán, A.
We present an analysis of infrared/optical/ultraviolet spectra of the two images of the first gravitationally lensed quasar Q0957 + 561A,B. The Hubble Space Telescope observations of Q0957 + 561A and Q0957 + 561B are separated in time by the known time delay in this system, so we can directly deduce the flux ratios. These flux ratios of images lea…
An XMM-Newton view of M101 - II. Global X-ray source properties
Warwick, R. S.; Roberts, T. P.; Ward, M. J. +2 more
We present the global X-ray properties of the point source population in the grand-design spiral galaxy M101, as seen with XMM-Newton. 108 X-ray sources are detected within the D25 ellipse of M101, of which ~24 are estimated to be background galaxies. Multiwavelength cross-correlations show that 20 sources are coincident with HII region…
XMM observations of the high-redshift quasar RXJ1028.6 - 0844 at z= 4.276: soft X-ray spectral flattening
Fabian, A. C.; Matsuoka, M.; Celotti, A. +2 more
We present results from a new XMM-Newton observation of the high-redshift quasar RXJ1028.6 - 0844 at a redshift of 4.276. The soft X-ray spectral flattening, as reported by a previous study with ASCA, is confirmed to be present, with, however, a reduced column density when modelled by absorption. The inferred column density for absorption intrinsi…
OH megamasers, starburst and AGN activity in Markarian 231
Knapen, J. H.; Richards, A. M. S.; Gray, M. D. +5 more
We present Multi-Element Radio-Linked Interferometer Network (MERLIN) observations of OH maser and radio continuum emission within a few hundred pc of the core of the ultraluminous infrared galaxy (ULIRG) Markarian 231. This is the only known OH megamaser galaxy classed as a Seyfert 1. Maser emission is identified with the 1665- and 1667-MHz trans…
Overtones of silicate and aluminate minerals and the 5-8 µm ice bands of deeply embedded objects
Hofmeister, A. M.; Bowey, J. E.
The distinct patterns, relatively low intensities and peak positions of overtone-combination bands of silicates and oxides suggest that the 5-8 µm spectral region can provide clues for the dust composition when near optically thick conditions exist for the 10-µm silicate feature. We present 1000-2500 cm-1 room-temperature la…
Luminosity segregation in three clusters of galaxies (A119, A2443, A2218)
Driver, Simon P.; De Propris, Roberto; Nulsen, Paul E. J. +2 more
We use deep wide-field V-band imaging obtained with the Wide Field Camera at the prime focus of the Issac Newton Telescope to study the spatial and luminosity distribution of galaxies in three low redshift (0.04 < z < 0.2) clusters: Abell 119, Abell 2443 and Abell 2218. The absolute magnitude limits probed in these clusters are MV…
Geometrical constraints upon the unipolar model of V407 Vul and RXJ0806.3+1527
Wilms, J.; Marsh, T. R.; Groot, P. +5 more
V407 Vul and RX J0806.3+1527 are X-ray emitting stars with X-ray light curves that are 100 per cent modulated on periods of 569 and 321 s, respectively. These periods and no others are also seen at optical and infrared wavelengths. These properties have led to the suggestion that the periods are the orbital periods of ultracompact pairs of white d…
New insights into the dust properties of the Taurus molecular cloud TMC-2 and its surroundings
del Burgo, C.; Laureijs, R. J.
We present ISOPHOT observations at 120 and 200 µm of a 31 × 57 arcmin2 region, with optical extinction AV ranging between ~ 0.5 and 11 mag, that encloses the Taurus molecular cloud TMC-2. The far-infrared emission is separated into a warm and a cold component using the ISOPHOT data and IRAS measurements at 60 and 100 &m…
Constraints on the distribution of absorption in the X-ray-selected AGN population found in the 13HXMM-Newton/Chandra deep field
McHardy, I.; Page, M. J.; Sasseen, T. +4 more
We present an analysis of the X-ray properties of sources detected in the 13HXMM-Newton deep (200-ks) field. In order to constrain the absorbed active galactic nuclei (AGN) population, we use extensive Monte Carlo simulations to compare directly the X-ray colours of observed sources with those predicted by several model distributions. I…
Simultaneous XMM-Newton and ESO VLT observations of supernova 1995N: probing the wind-ejecta interaction
Turatto, M.; Cappellaro, E.; Benetti, S. +3 more
We present the results of the first XMM-Newton observation of the interacting Type IIn supernova 1995N, performed in 2003 July. We find that the 0.2-10.0 keV unabsorbed flux dropped to a value of ~=1.8 × 10-13ergcm-2s-1, almost one order of magnitude lower than that of a previous ASCA observation of 1998 January. F…