Cookies

We use cookies to ensure that we give you the best experience on our website. You can change your cookie settings at any time. Otherwise, we'll assume you're OK to continue.


Durham Research Online
You are in:

Application of a relativistic accretion disc model to X-ray spectra of LMC X-1 and GRO J1655-40.

Gierliński, M. and Maciołek-Niedźwiecki, A. and Ebisawa, K. (2001) 'Application of a relativistic accretion disc model to X-ray spectra of LMC X-1 and GRO J1655-40.', Monthly notices of the Royal Astronomical Society., 325 (3). pp. 1253-1265.

Abstract

We present a general relativistic accretion disc model and its application to the soft-state X-ray spectra of black hole binaries. The model assumes a flat, optically thick disc around a rotating Kerr black hole. The disc locally radiates away the dissipated energy as a blackbody. Special and general relativistic effects influencing photons emitted by the disc are taken into account. The emerging spectrum, as seen by a distant observer, is parametrized by the black hole mass and spin, the accretion rate, the disc inclination angle and the inner disc radius. We fit the ASCA soft-state X-ray spectra of LMC X-1 and GRO J1655-40 by this model. We find that, having additional limits on the black hole mass and inclination angle from optical/UV observations, we can constrain the black hole spin from X-ray data. In LMC X-1 the constraint is weak, and we can only rule out the maximally rotating black hole. In GRO J1655-40 we can limit the spin much better, and we find 0.68a0.88. Accretion discs in both sources are radiation-pressure dominated. We do not find Compton reflection features in the spectra of any of these objects.

Item Type:Article
Keywords:Accretion discs, Relativity, Stars.
Full text:PDF - Other (416Kb)
Status:Peer-reviewed
Publisher Web site:http://dx.doi.org/10.1046/j.1365-8711.2001.04540.x
Publisher statement:The definitive version is available at www.blackwell-synergy.com
Record Created:28 Apr 2008
Last Modified:04 Aug 2011 14:48

Social bookmarking: del.icio.usConnoteaBibSonomyCiteULikeFacebookTwitterExport: EndNote, Zotero | BibTex
Usage statisticsLook up in GoogleScholar | Find in a UK Library