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The X-ray/gamma-ray spectrum of XTE J1550--564 in the very high state

Marek Gierlinski·Chris Done
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Abstract

We fit the broad-band X/gamma-ray spectrum (0.8-1000 keV) of the accreting black hole XTE J1550-564 in the very high state. The quasi-simultaneous data from ASCA, RXTE and OSSE show that the disc is strongly Comptonized, with a high energy tail extending out to several hundreds keV. However, inverse Compton scattering by a purely thermal or purely power-law electron distribution cannot explain the observed spectrum. Instead the data require a hybrid distribution, with both thermal and non-thermal electrons scattering the disc photons. This is very similar to the electron distribution inferred for other high and very high state black hole binaries, showing that it is a generic feature of high mass accretion rate black holes.

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Marek Gierlinski, Chris Done. 2003-03-12. The X-ray/gamma-ray spectrum of XTE J1550--564 in the very high state. https://doi.org/10.1046/j.1365-8711.2003.06591.x

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