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The first simultaneous X-ray/gamma-ray observations of Cyg X-1 by Ginga and OSSE

Marek Gierlinski·Andrzej A. Zdziarski·W. Neil Johnson·Bernard F. Phlips·Ken Ebisawa·Chris Done
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Abstract

We present the results of 4 simultaneous observations of Cygnus X-1 by Ginga and OSSE. The X-ray/gamma-ray spectra can be described by an intrinsic continuum and a component due to Compton reflection including an iron K-alpha line. The intrinsic spectrum at X-ray energies is a power-law with a photon spectral index of Gamma=1.6. The intrinsic gamma-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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Marek Gierlinski, Andrzej A. Zdziarski, W. Neil Johnson, Bernard F. Phlips, Ken Ebisawa, Chris Done. 1995-12-12. The first simultaneous X-ray/gamma-ray observations of Cyg X-1 by Ginga and OSSE. https://arxiv.org/abs/astro-ph/9512073

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