X-ray and gamma-ray spectra of Cyg X-1 in the soft state

Marek Gierlinski; Andrzej A. Zdziarski; Tadayasu Dotani; Ken Ebisawa; Keith Jahoda; W. Neil Johnson

doi:10.1063/1.54153

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arXiv · astro-ph/9707213

X-ray and gamma-ray spectra of Cyg X-1 in the soft state

Marek Gierlinski·Andrzej A. Zdziarski·Tadayasu Dotani·Ken Ebisawa·Keith Jahoda·W. Neil Johnson

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Abstract

We present X-ray/gamma-ray observations of Cyg X-1 in the soft state during 1996 May-June. We analyze ASCA, RXTE and OSSE data. The spectrum consists of soft X-ray blackbody emission of an optically thick accretion disk in the vicinity of a black hole and a power law with an energy index alpha around 1.2-1.5 extending to at least several hundred keV. In the spectra, we find the presence of strong Compton reflection, which probably comes from the disk.

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Marek Gierlinski, Andrzej A. Zdziarski, Tadayasu Dotani, Ken Ebisawa, Keith Jahoda, W. Neil Johnson. 1997-07-19. X-ray and gamma-ray spectra of Cyg X-1 in the soft state. https://doi.org/10.1063/1.54153

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