On the Interplay Between Radial and Angular Reflection Emissivity from the Black Hole Accretion Disc

0429140 - ASÚ 2015 RIV DE eng C - Conference Paper (international conference)
Svoboda, Jiří - Dovčiak, Michal - Goosmann, René - Karas, Vladimír
On the Interplay Between Radial and Angular Reflection Emissivity from the Black Hole Accretion Disc.
Relativity and Gravitation, 100 Years after Einstein in Prague. Cham: Springer International Publishing, 2014 - (Bičák, J.; Ledvinka, T.), s. 415-422. Springer Proceedings in Physics, 157. ISBN 978-3-319-06760-5. ISSN 0930-8989.
[100 Years after Einstein in Prague. Prague (CZ), 25.06.2012-29.06.2012]
Institutional support: RVO:67985815
Keywords : black holes * accretion disks
Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

Accretion processes around relativistic compact objects, such as black holes or neutron stars, can be well studied through X-ray spectroscopy. The disc reflection spectra detected in observations of several active galactic nuclei and X-ray binaries in our and nearby galaxies suggest high steepness of the radial emissivity. This can be primarily caused by compactness of the illuminating radiation. In our recent paper [1], we showed that the measurement of the steep radial emissivity index might also be over-estimated by ignoring the radial ionisation structure and the proper angular-emissivity law, which is non-trivial in the fully relativistic regime. In this paper, we demonstrate the interplay of the angular and radial emissivity. Employing an improper angular emissivity in the reflection models leads to over-estimated values for the black-hole angular momentum and the radial-emissivity index (by about 10 %).
Permanent Link: http://hdl.handle.net/11104/0234949