The broadband spectrum of Cygnus X-1

S. Fritz; J. Wilms; K. Pottschmidt; M. A. Nowak; E. Kendziorra; M. G. Kirsch; I. Kreykenbohm; A. Santangelo

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arXiv · 0706.2137

The broadband spectrum of Cygnus X-1

S. Fritz·J. Wilms·K. Pottschmidt·M. A. Nowak·E. Kendziorra·M. G. Kirsch·I. Kreykenbohm·A. Santangelo

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Abstract

The Black Hole (BH) binary Cygnus X-1 has been observed simultaneously by INTEGRAL, RXTE, and XMM-Newton for four times in November and December 2004, when Cyg X-1 became first observable with XMM-Newton. During these observations the source was found in one of its transitional states between the hard state and the soft state. We obtained a high signal to noise spectrum of Cyg X-1 from 3 keV to 1 MeV which allows us to put constraints on the nature of the Comptonizing plasma by modeling the continuum with Comptonization models as eqpair (Coppi 1992). Using XMM-Newton we were also able to confirm the presence of a relativistically broadened Fe K-alpha line.

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S. Fritz, J. Wilms, K. Pottschmidt, M. A. Nowak, E. Kendziorra, M. G. Kirsch, I. Kreykenbohm, A. Santangelo. 2007-06-14. The broadband spectrum of Cygnus X-1. https://arxiv.org/abs/0706.2137

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