Original title:
Understanding the iron K alpha line emissivity profile with GR radiative transfer code
Authors:
Zhang, Wenda ; Dovčiak, Michal ; Bursa, Michal ; Svoboda, Jiří ; Karas, Vladimír Document type: Papers Conference/Event: RAGtime /20.-22./, Opava (CZ), 20181015
Year:
2020
Language:
eng Abstract:
In this work, we present calculations of the illumination and the iron K alpha emissivity profiles performed with the GR radiative transfer code Monk that employs the Monte Carlo method. In most previous studies the distinction between the illumination and emissivity profiles was not clearly made. For AGN discs, the emissivity profile has a similar shape with the illumination profile, but in the inner most region the former is steeper than the latter, where as for accretion discs in black hole X-ray binaries, the distinction between the two profiles is more dramatic. We find out that the different behavior between AGN and black hole X-ray binary discs is due to the different energy spectra of the illuminating radiation. This suggests that the emissivity profile of the iron Kαline cannot be determined by black hole spin and corona geometry alone and the energy spectrum of the illuminating radiation has to be taken into account. We also study the dependence of the emissivity profile on the geometry of the corona.
Keywords:
accretion discs; emissivity profiles; radiative transfer Project no.: GA17-02430S (CEP) Funding provider: GA ČR Host item entry: Proceedings of RAGtime 20/22: Workshops on black holes and neutron stars, ISBN 978-80-7510-433-5