Testing slim-disk models on the thermal spectra of LMC X-3

0372104 - ASÚ 2012 RIV FR eng J - Journal Article
Straub, O. - Bursa, Michal - Sądowski, A. - Steiner, J.F. - Abramowicz, M. A. - Kluzniak, W. - McClintock, J.E. - Narayan, R. - Remillard, R.A.
Testing slim-disk models on the thermal spectra of LMC X-3.
Astronomy & Astrophysics. Roč. 533, September (2011), A67/1-A67/6. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA MŠMT(CZ) LC06014; GA MŠMT ME09036
Institutional research plan: CEZ:AV0Z10030501
Keywords : accretion * accretion disks * black hole physics
Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
Impact factor: 4.587, year: 2011

We have developed a new spectral model, slimbb, within the framework of XSPEC, which describes fully relativistic slim-disk accretion and includes photon ray-tracing that starts from the disk photosphere, rather than the equatorial plane. We demonstrate the features of this model by applying it to RXTE spectra of the persistent black-hole X-ray binary LMC X-3. LMC X-3 has the virtues of exhibiting large intensity variations while maintaining itself in soft spectral states which are well described using accretion-disk models, making it an ideal candidate to test the aptness of slimbb. Our results demonstrate consistency between the low-luminosity (thin-disk) and high luminosity (slim-disk) regimes. The results also illustrate that advection alone does not solve the problem of the origin of the surprisingly soft high-luminosity spectra in LMC X-3. We show that X-ray continuum-fitting in the high accretion rate regime can powerfully test black-hole accretion disk models.
Permanent Link: http://hdl.handle.net/11104/0205495