Search Publications
A comprehensive range of X-ray ionized-reflection models
Fabian, A. C.; Ross, R. R.
X-ray ionized reflection occurs when a surface is irradiated with X-rays so intense that its ionization state is determined by the ionization parameter ξ~F/n, where F is the incident flux and n the gas density. It occurs in accretion, on to compact objects including black holes in both active galaxies and stellar-mass binaries, and possibly in gam…
The unresolved hard X-ray background: the missing source population implied by the Chandra and XMM-Newton deep fields
Alexander, D. M.; Bauer, F. E.; Brandt, W. N. +6 more
We extend our earlier work on X-ray source stacking in the deep XMM-Newton observation of the Lockman Hole, to the 2-Ms Chandra Deep Field North (CDF-N) and the 1-Ms Chandra Deep Field South (CDF-S). The XMM-Newton work showed the resolved fraction of the X-ray background (XRB) to be ~80-100 per cent at <~ 2keV but this decreased to only ~50 pe…
MCG-6-30-15: long time-scale X-ray variability, black hole mass and active galactic nuclei high states
Uttley, P.; Goad, M. R.; McHardy, I. M. +1 more
We present a detailed study of the long time-scale X-ray variability of the Seyfert 1 Galaxy MCG-6-30-15, based on eight years of frequent monitoring observations with the Rossi X-ray Timing Explorer. When combined with the published short-time-scale XMM-Newton observations, we derive the power-spectral density (PSD) covering six decades of freque…
XMM-Newton spectroscopy of high-redshift quasars
O'Brien, P. T.; Reeves, J. N.; Page, K. L. +1 more
XMM-Newton observations of 29 high-redshift (z > 2) quasars, including seven radio-quiet, 16 radio-loud and six broad absorption line (BAL) objects, are presented; due to the high redshifts, the rest-frame energy bands extend up to ~30-70 keV. Over 2-10 keV, the quasars can be well fitted in each case by a simple power law, with no strong evide…
Evolution of X-ray emission from young massive star clusters
Oskinova, L. M.
The evolution of X-ray emission from young massive star clusters is modelled, taking into account the emission from the stars as well as from the cluster wind. It is shown that the level and character of the soft (0.2-10 keV) X-ray emission change drastically with cluster age and are tightly linked with stellar evolution. Using the modern X-ray ob…
New constraints on modified Newtonian dynamics from galaxy clusters
Silk, Joseph; Pointecouteau, Etienne
We revisit the application of modified Newtonian dynamics (MOND) to galaxy clusters. We confront the high-quality X-ray data for eight clusters of galaxies observed by the XMM-Newton satellite with the predictions of MOND. We obtain a ratio of the MOND dynamical mass to the baryonic mass of Mm/Mb= 4.94 +/- 0.50 in the outer p…
Physics of accretion in the millisecond pulsar XTE J1751-305
Gierliński, Marek; Poutanen, Juri
We have undertaken an extensive study of X-ray data from the accreting millisecond pulsar XTE J1751-305 observed by RXTE and XMM-Newton during its 2002 outburst. In all aspects this source is similar to the prototypical millisecond pulsar SAX J1808.4-3658, except for the higher peak luminosity of 13 per cent of Eddington, and the optical depth of …
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 …
X-ray reflection in the Seyfert galaxy 1H 0419-577 revealing strong relativistic effects in the vicinity of a Kerr black hole
Iwasawa, K.; Fabian, A. C.; Miniutti, G. +1 more
We report results obtained from six XMM-Newton observations of the Seyfert galaxy 1H 0419-577. The source was observed in a wide range of different flux levels, allowing its long-term spectral variability to be studied in detail, as already reported recently by Pounds et al. Here we show that the X-ray spectrum is well described by a simple two-co…