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arXiv · 0803.1725

Probing Clumpy Stellar Winds in SFXTs

R. Walter·J. Zurita-Heras
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Abstract

Quantitative constraints on the wind clumping of massive stars can be obtained from the study of the hard X-ray variability of SFXTs. In these systems, a large fraction of the hard X-ray emission is emitted in the form of flares with typical duration of 3 ksec, frequency of 7 days and luminosity of $10^{36}$ ergs/s. Such flares are most probably emitted by the interaction of a compact object orbiting at $\sim10$ R$_*$ with wind clumps ($10^{22-23}$ g). The density ratio between the clumps and the inter-clump medium is $10^{2-4}$ . The parameters of the clumps and of the inter-clump medium are in good agreement with macro-clumping scenario and line-driven instability simulations.

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R. Walter, J. Zurita-Heras. 2008-03-12. Probing Clumpy Stellar Winds in SFXTs. https://doi.org/10.1063/1.2945056

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