Search Publications
An XMM-Newton spectral survey of 12 µm selected galaxies - I. X-ray data
Nandra, Kirpal; Brightman, Murray
We present an X-ray spectral analysis of 126 galaxies of the 12 µm galaxy sample. By studying this sample at X-ray wavelengths, we aim to determine the intrinsic power, continuum shape and obscuration level in these sources. We improve upon previous works by the use of superior data in the form of higher signal-to-noise ratio spectra, finer …
The causal connection between disc and power-law variability in hard state black hole X-ray binaries
Wilms, J.; Uttley, P.; Pottschmidt, K. +4 more
We use the XMM-Newton EPIC-pn instrument in timing mode to extend spectral time-lag studies of hard state black hole X-ray binaries into the soft X-ray band. We show that variations of the disc blackbody emission substantially lead variations in the power-law emission, by tenths of a second on variability time-scales of seconds or longer. The larg…
X-ray spectroscopy of the Virgo Cluster out to the virial radius
Böhringer, H.; Simionescu, A.; Allen, S. W. +2 more
We present results from the analysis of a mosaic of 13 XMM-Newton pointings covering the Virgo Cluster from its centre northwards out to a radius r∼ 1.2 Mpc (∼4?5), reaching the virial radius and beyond. This is the first time that the properties of a modestly sized (Mvir∼ 1.4 × 1014 M⊙, kT∼ 2.3 keV), dynamically y…
2XMM ultraluminous X-ray source candidates in nearby galaxies
Roberts, T. P.; Mateos, S.; Walton, D. J. +1 more
Ultraluminous X-ray sources (ULXs) are some of the most enigmatic X-ray bright sources known to date. It is generally accepted that they cannot host black holes as large as those associated with active galaxies, but they appear to be significantly more luminous than their better understood Galactic X-ray binary (XRB) cousins, while displaying an i…
A wide Chandra view of the core of the Perseus cluster
Churazov, E.; Young, A. J.; Fabian, A. C. +12 more
We present new Chandra images of the X-ray emission from the core of the Perseus cluster of galaxies. The total observation time is now 1.4 Ms. New depressions in X-ray surface brightness are discovered to the north of NGC 1275, which we interpret as old rising bubbles. They imply that bubbles are long-lived and do not readily breakup when rising …
X-ray absorption by broad-line region clouds in Mrk 766
Maiolino, R.; Elvis, M.; Fabbiano, G. +5 more
We present a new analysis of a 9-d long XMM-Newton monitoring of the narrow-line Seyfert 1 galaxy Mrk 766. We show that the strong changes in the spectral shape, which occurred during this observation, can be interpreted as due to broad-line region clouds crossing the line of sight to the X-ray source. Within the occultation scenario, the spectral…
Determination of the X-ray reflection emissivity profile of 1H 0707-495
Fabian, A. C.; Wilkins, D. R.
When considering the X-ray spectrum resulting from the reflection off the surface of accretion discs of AGN, it is necessary to account for the variation in reflected flux over the disc, i.e. the emissivity profile. This will depend on factors including the location and geometry of the X-ray source and the disc characteristics. We directly obtain …
Constraints on turbulent velocity broadening for a sample of clusters, groups and elliptical galaxies using XMM-Newton
Fabian, A. C.; Sanders, J. S.; Smith, R. K.
Using the width of emission lines in XMM-Newton Reflection Grating Spectrometer spectra, we place direct constraints on the turbulent velocities of the X-ray emitting medium in the cores of 62 galaxy clusters, groups and elliptical galaxies. We find five objects where we can place an upper limit on the line-of-sight broadening of 500 km s-1
The energy source of the filaments around the giant galaxy NGC 1275
Fabian, A. C.; Ferland, G. J.; Sanders, J. S. +3 more
The brightest galaxy in the nearby Perseus cluster, NGC 1275, is surrounded by a network of filaments. These were first observed through their Hα emission but are now known to have a large molecular component with a total mass approaching 1011 M⊙ of gas. The filaments are embedded in hot intracluster gas and stretch over 80 k…
Early magnetic B-type stars: X-ray emission and wind properties
Hamann, W. -R.; Oskinova, L. M.; Ignace, R. +3 more
We present a comprehensive study of X-ray emission by, and wind properties of, massive magnetic early B-type stars. Dedicated XMM-Newton observations were obtained for three early-type B-type stars, ξ1 CMa, V2052 Oph and ζ Cas, with recently discovered magnetic fields. We report the first detection of X-ray emission from V2052 Oph and ζ…