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OSSE and RXTE Observations of GRS 1915+105: Evidence for Non-thermal Comptonization

Andrzej A. Zdziarski·J. Eric Grove·Juri Poutanen·A. R. Rao·S. V. Vadawale
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Abstract

GRS 1915+105 was observed by the CGRO/OSSE 9 times in 1995-2000, and 8 of those observations were simultaneous with those by RXTE. We present an analysis of all of the OSSE data and of two RXTE-OSSE spectra with the lowest and highest X-ray fluxes. The OSSE data show a power-law--like spectrum extending up to ~600 keV without any break. We interpret this emission as strong evidence for the presence of non-thermal electrons in the source. The broad-band spectra cannot be described by either thermal or bulk-motion Comptonization, whereas they are well described by Comptonization in hybrid thermal/ non-thermal plasmas.

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Andrzej A. Zdziarski, J. Eric Grove, Juri Poutanen, A. R. Rao, S. V. Vadawale. 2001-05-11. OSSE and RXTE Observations of GRS 1915+105: Evidence for Non-thermal Comptonization. https://doi.org/10.1086/320932

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