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arXiv · 1510.08902

High ionisation absorption in low mass X-ray binaries

G. Ponti·S. Bianchi·T. Munoz-Darias·K. De·R. P. Fender·A. Merloni
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Abstract

The advent of the new generation of X-ray telescopes yielded a significant step forward in our understanding of ionised absorption generated in the accretion discs of X-ray binaries. It has become evident that these relatively weak and narrow absorption features, sporadically present in the X-ray spectra of some systems, are actually the signature of equatorial outflows, which might carry away more matter than that being accreted. Therefore, they play a major role in the accretion phenomenon. These outflows (or ionised atmospheres) are ubiquitous during the softer states but absent during the power-law dominated, hard states, suggesting a strong link with the state of the inner accretion disc, presence of the radio-jet and the properties of the central source. Here, we discuss the current understanding of this field.

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G. Ponti, S. Bianchi, T. Munoz-Darias, K. De, R. P. Fender, A. Merloni. 2015-10-29. High ionisation absorption in low mass X-ray binaries. https://doi.org/10.1002/asna.201612339

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