Search Publications
The ultraluminous state
Done, Chris; Roberts, Timothy P.; Gladstone, Jeanette C.
We revisit the question of the nature of ultraluminous X-ray sources (ULXs) through a detailed investigation of their spectral shape, using the highest quality X-ray data available in the XMM-Newton public archives (>~10000 counts in their EPIC spectrum). We confirm that simple spectral models commonly used for the analysis and interpretation o…
Simultaneous X-ray/optical/UV snapshots of active galactic nuclei from XMM-Newton: spectral energy distributions for the reverberation mapped sample
Fabian, A. C.; Vasudevan, R. V.
We employ contemporaneous optical, ultraviolet (UV) and X-ray observations from the XMM-Newton European Photon Imaging Camera (EPIC-pn) and Optical Monitor (OM) archives to present, for the first time, simultaneous spectral energy distributions (SEDs) for the majority of the Peterson et al. reverberation mapped sample of active galactic nuclei (AG…
The active nuclei of z < 1.0 3CRR radio sources
Hardcastle, M. J.; Croston, J. H.; Evans, D. A.
We combine Chandra and XMM-Newton X-ray data from our previous papers with new X-ray observations and with Spitzer mid-infrared (mid-IR) data in order to study the nature of the nuclei of radio galaxies and radio-loud quasars with z < 1.0 from the 3CRR sample. The significant increase in sample size over our previous work, the reduction of bias…
Accretion disc variability in the hard state of black hole X-ray binaries
Wilkinson, Tony; Uttley, Philip
XMM-Newton X-ray spectra of the hard state black hole X-ray binaries (BHXRBs) SWIFTJ1753.5-0127 and GX339-4 show evidence for accretion disc blackbody emission, in addition to hard power laws. The soft and hard band power spectral densities (PSDs) of these sources demonstrate variability over a wide range of time-scales. However, on time-scales of…
The XMM-Newton long look of NGC 1365: uncovering of the obscured X-ray source
Zezas, A.; Bianchi, S.; Guainazzi, M. +10 more
We present an analysis of the extreme obscuration variability observed during an XMM-Newton 5-d continuous monitoring of the active galactic nuclei (AGN) in NGC 1365. The source was in a reflection-dominated state in the first ~1.5 d, then a strong increase in the 7-10 keV emission was observed in ~10 h, followed by a symmetric decrease. The spect…
Spectral variability of ultraluminous X-ray sources
Poutanen, Juri; Kajava, Jari J. E.
We study spectral variability of 11 ultraluminous X-ray sources (ULX) using archived XMM-Newton and Chandra observations. We use three models to describe the observed spectra: a power law, a multicolour disc (MCD) and a combination of these two models. We find that seven ULXs show a correlation between the luminosity LX and the photon i…
3D modelling of the colliding winds in η Carinae - evidence for radiative inhibition
Corcoran, M. F.; Hamaguchi, K.; Pittard, J. M. +2 more
The X-ray emission from the supermassive star ηCar is simulated using a 3D model of the wind-wind collision. In the model the intrinsic X-ray emission is spatially extended and energy dependent. Absorption due to the unshocked stellar winds and the cooled post-shock material from the primary LBV star is calculated as the intrinsic emission is ray …
Determining the spin of two stellar-mass black holes from disc reflection signatures
Fabian, A. C.; Miller, J. M.; Reis, R. C. +1 more
We present measurements of the dimensionless spin parameters and inner-disc inclination of two stellar-mass black holes. The spin parameter of SWIFT J1753.5-0127 and GRO J1655-40 is estimated by modelling the strong reflection signatures present in their XMM-Newton observations. Using a newly developed, self-consistent reflection model which inclu…
Constraints on turbulent pressure in the X-ray haloes of giant elliptical galaxies from resonant scattering
Simionescu, A.; Kaastra, J. S.; Churazov, E. +5 more
The dense cores of X-ray emitting gaseous haloes of large elliptical galaxies with temperatures kT <~ 0.8 keV show two prominent FeXVII emission features, which provide a sensitive diagnostic tool to measure the effects of resonant scattering. We present here high-resolution spectra of five bright nearby elliptical galaxies, obtained with the r…
The first outburst of the new magnetar candidate SGR0501+4516
Campana, S.; Tiengo, A.; Hurley, K. +17 more
We report here on the outburst onset and evolution of the new soft gamma-ray repeater SGR0501+4516. We monitored the new SGR with XMM-Newton starting on 2008 August 23, 1 day after the source became burst active, and continuing with four more observations in the following month, with the last one on 2008 September 30. Combining the data with the S…