The first simultaneous X-ray/γ-ray observations of Cyg X-1 by Ginga and OSSE
نویسندگان
چکیده
We present the results of 4 simultaneous observations of Cygnus X-1 by Ginga and OSSE. The X-ray/γray spectra can be described by an intrinsic continuum and a component due to Compton reflection including an iron Kα line. The intrinsic spectrum at X-ray energies is a power-law with a photon spectral index of Γ = 1.6. The intrinsic γ-ray spectrum can be phenomenologically described by either a power-law without cutoff up to 150 keV, and an exponential cutoff above that energy, or by an exponentially cutoff power law and a second hard component.
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