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XMM–Newton observations of the brightest ultraluminous X-ray sources
We present an analysis of 13 of the best quality ultraluminous X-ray source (ULX) data sets available from XMM‐Newton European Photon Imaging Camera (EPIC) observations. We utilize the high
XMM-EPIC observation of MCG-6-30-15: direct evidence for the extraction of energy from a spinning black hole?
We present XMM-Newton European Photon Imaging Camera (EPIC) observations of the bright Seyfert 1 galaxy MCG 6-30-15, focusing on the broad Fe Kline at � 6keV and the associated reflection continuum,
An accreting pulsar with extreme properties drives an ultraluminous x-ray source in NGC 5907
Observations showing that NGC 5907 ULX is instead an x-ray accreting neutron star (NS) with a spin period evolving from 1.43 seconds in 2003 to 1.13 seconds in 2014 suggest that other extreme ULXs (x-ray luminosity ≥ 1041 erg second−1) might harbor NSs.
Long term variability of Cygnus X-1. I. X-ray spectral-temporal correlations in the hard state
We present the long term evolution of the timing properties of the black hole candidate Cygnus X-1 in the 0.002-128 Hz frequency range as monitored from 1998 to 2001 with the Rossi X-ray Timing
Low-Luminosity States of the Black Hole Candidate GX 339–4. I. ASCA and Simultaneous Radio/RXTE Observations
We discuss a series of observations of the black hole candidate GX 339(4 in low-luminosity, spec- trally hard states. We present spectral analysis of three separate archival Advanced Satellite for
The Hot and Energetic Universe: A White Paper presenting the science theme motivating the Athena+ mission
This White Paper, submitted to the recent ESA call for science themes to define its future large missions, advocates the need for a transformational leap in our understanding of two key questions in
Low-Luminosity States of the Black Hole Candidate GX 339–4. II. Timing Analysis
Here we present timing analysis of a set of eight Rossi X-Ray Timing Explorer (RXTE) observations of the black hole candidate GX 339-4 that were taken during its hard/low state. On long timescales,
The causal connection between disc and power-law variability in hard state black hole X-ray binaries
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
High variability in Vela X-1: giant flares and off states
Aims. We investigate the spectral and temporal behavior of the high mass X-ray binary Vela X-1 during a phase of high activity, with special focus on the observed giant flares and off states.
The variable cyclotron line in GX 301-2
We present pulse phase resolved spectra of the hypergiant high mass X-ray binary GX 301−2. We observed the source in 2001 October with RXTE continuously for a total on-source time of almost 200 ks.