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Broad-band Spectral Properties of Accreting X-ray Binary Pulsars

Mauro Orlandini
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Abstract

Broad-band spectra of accreting X-ray binary pulsars can be fit by a phenomenological model composed by a power law with a high energy rollover above 10 keV, plus a blackbody component with a temperature of few hundred eV. While, at least qualitatively, the hard tail can be explained in terms of (inverse) Compton scattering, the origin of the soft component cannot find a unique explanation. Recently a qualitative picture able to explain the overall broad band-spectrum of luminous X-ray pulsars was carried out by taking into account the effect of bulk Comptonization in the accretion column. After a review on these recent theoretical developments, I will present a case study of how different modelization of the continuum affect broad features, in particular the cyclotron resonance features in Vela X-1.

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Mauro Orlandini. 2005-10-10. Broad-band Spectral Properties of Accreting X-ray Binary Pulsars. https://doi.org/10.1016/j.asr.2006.04.026

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