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Strongly absorbed quiescent X-ray emission from the X-ray transient XTE J0421+56

L. Boirin·A. N. Parmar·D. Lumb·M. Orlandini·N. Schartel
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Abstract

We have observed the soft X-ray transient XTE J0421+56 in quiescence with XMM-Newton. The observed spectrum is highly unusual being dominated by a broad feature at 6.5 keV and can be modeled by a strongly absorbed continuum. The spectra of X-ray transients observed so far are normally modeled using Advection Dominated Accretion Flow models, black-bodies, power-laws, or by the thermal emission from a neutron star surface. The strongly absorbed X-ray emission of XTE J0421+56 could result from the compact object being embedded within the dense circumstellar wind emitted from the supergiant B[e] companion star.

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L. Boirin, A. N. Parmar, D. Lumb, M. Orlandini, N. Schartel. 2002-02-01. Strongly absorbed quiescent X-ray emission from the X-ray transient XTE J0421+56. https://arxiv.org/abs/astro-ph/0202029

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