Analysis of NuSTAR and Suzaku observations of Cyg X-1 in the hard state: evidence for a truncated disc geometry

  title={Analysis of NuSTAR and Suzaku observations of Cyg X-1 in the hard state: evidence for a truncated disc geometry},
  author={Rupal Basak and Andrzej A. Zdziarski and Michael L. Parker and Nazma Islam},
  journal={Monthly Notices of the Royal Astronomical Society},
The geometry of the accretion flow in black hole X-ray binaries in the hard state, in particular the position of the disc inner edge, has been a subject of intense debate in recent years. We address this issue by performing a spectral study of simultaneous observations of Cyg X-1 in the hard state by NuSTAR and Suzaku. The same data were analysed before, and modelled by a lamppost containing hybrid electrons and located very close to the horizon, whose emission was incident on a surrounding… 

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