Fitting the Cyg X - 1 Spectrum

نویسندگان

  • A. Crider
  • E. P. Liang
  • I. A. Smith
  • D. Lin
  • M. Kusunose
چکیده

Using Monte Carlo methods to simulate the inverse Compton scattering of soft photons, we model the spectrum of the Galactic black hole candidate Cyg X-1, which shows evidence of a nonthermal tail extending beyond a few hundred keV. We assume an ad hoc sphere of leptons, whose energy distribution consists of a Maxwellian plus a high energy power-law tail, and inject 0.5 keV blackbody photons. The spectral data is used to constrain the nonthermal plasma fraction and the power-law index assuming a reasonable Maxwellian temperature and Thomson depth. A small but non-negligible fraction of nonthermal leptons is needed to explain the power-law tail.

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تاریخ انتشار 1997