Analyzing X-Ray Variability of Cygnus X-1

  • Katja Pottschmidt
  • Michael König
Conference paper
Part of the Astrophysics and Space Science Library book series (ASSL, volume 218)


With a mass of ≈ 10 M the compact object of the high mass X-ray binary Cyg X-1 is one of the best established black hole candidates (BHCs). Its characteristic short-term variability is studied in order to acquire better insight into the accretion process. Cyg X-1 was the first source for which X-ray variability on time scales < 1s was detected (Oda et al. 1971). Today we know that binaries containing a neutron star can also show this behaviour but the efforts in trying to identify a BHC by its short-term variability are continuing. During the observations with the EXOSAT ME experiment Cyg X-1 was in its low (hard) state as it is most of the time. Typical temporal structures are shown in Fig. 1.


Neutron Star Shot Noise Compact Object Accretion Process Single Relaxation Time 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media Dordrecht 1997

Authors and Affiliations

  • Katja Pottschmidt
    • 1
  • Michael König
    • 1
  1. 1.Institut für Astronomie und Astrophysik — AstronomieUniversität TübingenGermany

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