Transient outburst mechanisms in Supergiant Fast X-ray Transients

L. Sidoli

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arXiv · 0809.3157

Transient outburst mechanisms in Supergiant Fast X-ray Transients

L. Sidoli

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Abstract

The recent discovery of a new class of recurrent and fast X-ray transient sources, the Supergiant Fast X-ray Transients, poses interesting questions on the possible mechanisms responsible for their transient X-ray emission. The association with blue supergiants, the spectral properties similar to those of accreting pulsars and the detection, in a few cases, of X-ray pulsations, confirm that these transients are High Mass X-ray Binaries. I review the different mechanisms proposed to explain their transient outbursts and the link to persistent wind accretors. I discuss the different models in light of the new observational results coming from an on-going monitoring campaign of four Supergiant Fast X-ray Transients with Swift.

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L. Sidoli. 2009-02-17. Transient outburst mechanisms in Supergiant Fast X-ray Transients. https://arxiv.org/abs/0809.3157

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