Catching Up on State Transitions in Cygnus X-1 (2008)
Boeck, Moritz, Hanke, Manfred, Wilms, Joern, Grinberg, Victoria, Pottschmidt, Katja, Markoff, Sera, ...
In 2005 February we observed Cygnus X-1 over a period of 10 days quasi-continuously with the Rossi X-ray Timing Explorer and the Ryle telescope. We present the results of the spectral and timing...
Multi-Satellite Observations of Cygnus X-1 to Study the Focused Wind and Absorption Dips (2008)
Hanke, Manfred, Wilms, Joern, Boeck, Moritz, Nowak, Michael A., Schulz, Norbert S., Pottschmidt, Katja, ...
High-mass X-ray binary systems are powered by the stellar wind of their donor stars. The X-ray state of Cygnus X-1 is correlated with the properties of the wind which defines the environment of mass...
High variability in Vela X-1: giant flares and off states (2008)
Kreykenbohm, Ingo, Wilms, Joern, Kretschmar, Peter, Torrejon, Jose Miguel, Pottschmidt, Katja, Hanke, Manfred, ...
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. INTEGRAL...
Hanke, Manfred, Wilms, Joern, Nowak, Michael A., Pottschmidt, Katja, Schulz, Norbert S., Lee, Julia C.
We present analyses of a 50 ks observation of the supergiant X-ray binary system Cygnus X-1/HDE 226868 taken with the Chandra High Energy Transmission Grating Spectrometer (HETGS). Cyg X-1 was in its...
Wilms, Joern, Pottschmidt, Katja, Pooley, Guy G., Markoff, Sera, Nowak, Michael A., Kreykenbohm, Ingo, ...
We report on the first detection of a quasi-simultaneous radio-X-ray flare of Cygnus X-1. The detection was made on 2005 April 16 with pointed observations by the Rossi X-ray Timing Explorer and the...
Is the `IR Coincidence' Just That? (2005)
Nowak, Michael, Wilms, Joern, Heinz, Sebastian, Pooley, Guy, Pottschmidt, Katja, Corbel, Stephane
(Abridged) Motch (1985) suggested that in the hard state of GX 339-4 the soft X-ray power-law extrapolated backward in energy agrees with the IR flux. Corbel & Fender (2002) showed that the hard...
Is the ``IR Coincidence'' just that? (2005)
Nowak, Michael A., Wilms, Jörn, Heinz, Sebastian, Pooley, Guy, Pottschmidt, Katja, Corbel, Stephane
INTEGRAL Cross-calibration Status (2004)
Lubinski, Piotr, Dubath, Pierre, Kretschmar, Peter, Pottschmidt, Katja, Walter, Roland
The status of the INTEGRAL cross-calibration is presented for a standard X-ray astronomy source, the Crab Nebula, as well as for some weaker sources. The relative flux normalization for the different...
INTEGRAL cross-calibration status (2004)
Lubiński, Piotr, Dubath, Pierre, Kretschmar, Peter, Pottschmidt, Katja, Walter, Roland
Accretion Disk Weather of Black Hole X-Ray Binaries - The Case of Cygnus X-1 (2003)
Die Röntgenemission, die bei der Akkretion von Materie auf einSchwarzes Loch entsteht, bietet die Möglichkeit, den Einfluss dieserObjekte auf ihre Umgebung zu untersuchen. Der Schwerpunkt...
Accretion disk weather of black hole X-ray binaries : the case of cygnus X-1 / (2002)
Zugl.: Tübingen, Univ., Diss., 2002.
X-Ray Observations of XTE J1550-564 During the Decay of the 2000 Outburst - II. Timing (2001)
Kalemci, Emrah, Tomsick, John A., Rothschild, R. E., Pottschmidt, Katja, Kaaret, Philip
We investigate the timing behavior of XTE J1550-564 with the Rossi X-ray Timing Explorer (RXTE) as the source made a transition to the hard state during the decay of the 2000 outburst. We detect a...
Katja Pottschmidt, Michael Konig
. Cyg X-1 exhibits X-ray variability on all measured time scales. The observed short-term behaviour is usually described by shot noise models, which assume that the lightcurve is produced by...