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arXiv · 1004.1117

A Thorough Look at the Photoionized Wind and Absorption Dips in the Cygnus X-1 / HDE 226868 X-ray Binary System

Manfred Hanke·Jörn Wilms·Michael A. Nowak·Laura Barragán·Katja Pottschmidt·Norbert S. Schulz·Julia C. Lee
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Abstract

We present results from simultaneous observations of the high-mass X-ray binary system Cygnus X-1 / HDE 226868 with Suzaku, Chandra-HETGS, XMM-Newton, RXTE, INTEGRAL, and Swift in 2008 April. Performed shortly after orbital phase 0, when our line of sight to the black hole passes through the densest part of the O-star's wind, these obervations show common transient absorption dips in the soft X-ray band. For the first time, however, we detect a simultaneous scattering trough in the hard X-ray light curves. The more neutral clump is thus only the core of a larger ionized blob, which contains a significant fraction of the total wind mass. The diluted wind outside of these clumps is almost completely photoionized.

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Manfred Hanke, Jörn Wilms, Michael A. Nowak, Laura Barragán, Katja Pottschmidt, Norbert S. Schulz, Julia C. Lee. 2010-04-07. A Thorough Look at the Photoionized Wind and Absorption Dips in the Cygnus X-1 / HDE 226868 X-ray Binary System. https://arxiv.org/abs/1004.1117

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