Spectral fit of Cygnus X-1 in high energy— a self-consistent study

Conference paper


We fit the spectra of Cyg X-1 using two component advective flows with Keplerian accretion disks on the equatorial plane surrounded by sub-Keplerian disks when standing shocks are present. The soft photons generated by the bremsstrahlung and synchrotron processes in the sub-Keplerian flow, as well as the multi-colour black body emission from the Keplerian disk are Comptonized by the thermal and non-thermal electrons. By varying Keplerian and sub-Keplerian rates we are able to reproduce the observed soft and hard states as far as X-ray region is concerned and ‘low γ-ray intensity’ and ‘high γ-ray intensity’ states as far as the soft γ-ray region is concerned. We also find two pivotal points where the spectra intersect as is observed in Cyg X-1.


Physics of black holes Accretion and accretion disks X-ray sources 


04.70.-s 97.10.Gz 98.70.Qy 


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Copyright information

© Springer 2007

Authors and Affiliations

  1. 1.Centre for Space PhysicsKolkataIndia
  2. 2.S.N. Bose National Centre for Basic SciencesKolkataIndia

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