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arXiv · 1106.0009

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

Odele Straub·Michal Bursa·Aleksander Sadowski·James F. Steiner·Marek A. Abramowicz·Wlodzimierz Kluzniak·Jeffrey E. McClintock·Ramesh Narayan·Ronald A. Remillard
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Abstract

Slim-disk models describe accretion flows at high luminosities, while reducing to the standard thin disk form in the low luminosity limit. 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. We also show that X-ray continuum-fitting in the high accretion rate regime can powerfully test black-hole accretion disk models.

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Odele Straub, Michal Bursa, Aleksander Sadowski, James F. Steiner, Marek A. Abramowicz, Wlodzimierz Kluzniak, Jeffrey E. McClintock, Ramesh Narayan, Ronald A. Remillard. 2011-05-31. Testing slim-disk models on the thermal spectra of LMC X-3. https://doi.org/10.1051/0004-6361%2F201117385

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