Accretion Disc Thermal Reverberation in the Lamp Post Geometry †
1
Department of Physics and Institute of Theoretical and Computational Physics, University of Crete, 71003 Heraklion, Greece
2
Foundation for Research and Technology—Hellas, IESL, Voutes, 71110 Heraklion, Greece
3
Institute of Astrophysics, FORTH, GR-71110 Heraklion, Greece
4
Department of Astronomy, University of Michigan, 1085 South University Avenue, Ann Arbor, MI 48109-1107, USA
5
Astronomical Institute of the Academy of Sciences, Boční II 1401, CZ-14100 Prague, Czech Republic
*
Author to whom correspondence should be addressed.
†
Presented at the meeting Recent Progress in Relativistic Astrophysics, Shanghai, China, 6–8 May 2019.
Proceedings 2019, 17(1), 12; https://doi.org/10.3390/proceedings2019017012
Published: 18 October 2019
(This article belongs to the Proceedings of Recent Progress in Relativistic Astrophysics)
Abstract
We present results regarding the disc response functions and the corresponding time lags assuming a standard Novikov–Thorne accretion disc illuminated by a point-like X-ray source. We took into account all relativistic effects in the light propagation from the X-ray source to the disc and then to the observer, and we computed the disc reflection, accounting for its radial ionization profile. Our results suggest that the thermal reverberation effects should be stronger in sources with large X-ray source height and low accretion rate. We found that time lags increase with height and accretion rate. The amplitude of the observed time lags as a function of wavelength (in NGC 5548) is consistent with the model predictions. It is not necessary for the disc to be too hot, it may be that the X-ray source is located further from the disc.
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MDPI and ACS Style
Papadakis, I.E.; Kammoun, E.S.; Dovčiak, M. Accretion Disc Thermal Reverberation in the Lamp Post Geometry. Proceedings 2019, 17, 12. https://doi.org/10.3390/proceedings2019017012
AMA Style
Papadakis IE, Kammoun ES, Dovčiak M. Accretion Disc Thermal Reverberation in the Lamp Post Geometry. Proceedings. 2019; 17(1):12. https://doi.org/10.3390/proceedings2019017012
Chicago/Turabian StylePapadakis, Iossif E., Elias S. Kammoun, and Michal Dovčiak. 2019. "Accretion Disc Thermal Reverberation in the Lamp Post Geometry" Proceedings 17, no. 1: 12. https://doi.org/10.3390/proceedings2019017012
