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Discovery of complex narrow X-ray absorption features from the low-mass X-ray binary GX13+1 with XMM-Newton

L. Sidoli·A. N. Parmar·T. Oosterbroek·D. Lumb
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Abstract

We report the detection of a complex of narrow X-ray absorption features from the low-mass X-ray binary GX13+1 during 3 XMM-Newton observations in 2000 March and April. The features are consistent with being due to resonant scattering of the K_alpha and K_beta lines of He- and H-like iron (Fe xxv and Fe xxvi) and H-like calcium (Ca xx) K_alpha. Only the Fe xxvi K_alpha line has been previously observed from GX13+1. Due to the closeness in energy the Fe xxv and Fe xxvi K_beta features may also be ascribed to Nixxvii and Nixxviii K_alpha, respectively. We also find evidence for the presence of a deep (tau~0.2) Fe xxv absorption edge at 8.83 keV. The equivalent widths of the lines do not show any obvious variation on a timescale of a few days suggesting that the absorbing material is a stable feature of the system and present during a range of orbital phases.

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L. Sidoli, A. N. Parmar, T. Oosterbroek, D. Lumb. 2002-02-04. Discovery of complex narrow X-ray absorption features from the low-mass X-ray binary GX13+1 with XMM-Newton. https://doi.org/10.1051/0004-6361%3A20020192

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