A comparative analysis of standard accretion disks spectra: an application to Ultraluminous X-ray Sources - Astrophysics > High Energy Astrophysical PhenomenaReport as inadecuate




A comparative analysis of standard accretion disks spectra: an application to Ultraluminous X-ray Sources - Astrophysics > High Energy Astrophysical Phenomena - Download this document for free, or read online. Document in PDF available to download.

Abstract: We compare standard models of accretion disks around black holes that includethe appropriate zero-torque inner boundary condition and relativistic effectson the emission and propagation of radiation. The comparison is performedadopting the multicolor disk blackbody model MCD as reference and looking forthe parameter space in which it is in statistical agreement with -morephysical- accretion disk models. We find simple -recipes- that can be used foradjusting the estimates of the physical inner radius of the disk, the blackhole mass and the accretion rate inferred using the parameters of the MCD fits.We applied these results to four ULXs for which MCD spectral fits of theirX-ray soft spectral components have been published and find that, in threecases NGC 1313 X-1, X-2 and M 81 X-9, the black hole masses inferred for astandard disk around a Schwarzschild black hole are in the interval ~100-200solar masses. Only if the black hole is maximally rotating are the massescomparable to the much larger values previously derived in the literature.



Author: A. Lorenzin, L. Zampieri

Source: https://arxiv.org/







Related documents