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The broad-band X-ray spectrum of the dipping Low Mass X-ray Binary EXO0748--676

Lara Sidoli·Arvind N. Parmar·Tim Oosterbroek
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Abstract

We present results of a 0.1-100 keV BeppoSAX observation of the dipping LMXRB EXO 0748-676 performed in 2000 November. During the observation the source exhibited X-ray eclipses, type I X-ray bursts and dipping activity over a wide range of orbital phases. The 0.1-100keV "dip-free"(ie. dipping and eclipsing intervals excluded) spectrum is complex,especially at low-energies where a soft excess is present. Two very different spectral models give satisfactory fits. The first is the progressive covering model, consisting of separately absorbed black body and cut-off power-law components.The second model is an absorbed cut-off power-law together with a moderately ionized absorber with a sub-solar abundance of Fe and a 2.13 keV absorption feature (tentatively identified with Si xiii). This ionized absorber may be the same feature as seen by Chandra during dips from EXO 0748-676.

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Lara Sidoli, Arvind N. Parmar, Tim Oosterbroek. 2004-08-23. The broad-band X-ray spectrum of the dipping Low Mass X-ray Binary EXO0748--676. https://doi.org/10.1051/0004-6361%3A20047023

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