Volume 441, Number 3, October III 2005
|Page(s)||855 - 861|
|Published online||23 September 2005|
The relativistic shift of narrow spectral features from black-hole accretion discs
Charles University, Faculty of Mathematics and Physics, V Holešovičkách 2, 180 00 Prague, Czech Republic
2 Astronomical Institute, Academy of Sciences, Boční II, 141 31 Prague, Czech Republic e-mail: email@example.com
3 Dipartimento di Fisica, Università degli Studi “Roma Tre”, via della Vasca Navale 84, 00146 Roma, Italy
Accepted: 14 June 2005
Transient spectral features have been discovered in the X-ray spectra of Active Galactic Nuclei, mostly in the 5–7 keV energy range. Several interpretations were proposed for the origin of these features. We examined a model of Doppler boosted blue horns of the iron line originating from a spot in a black hole accretion disc, taking into account different approximations of general relativistic light rays and the resulting shift of energy of photons. We provide a practical formula for the blue horn energy of an intrinsically narrow line and assess its accuracy by comparing the approximation against an exact value, predicted under the assumption of a planar accretion disc. The most accurate approximation provides excellent agreement with the spot orbital radius down to the marginally stable orbit of a non-rotating black hole.
Key words: line: profiles / accretion, accretion discs / black hole physics / X-rays: galaxies
© ESO, 2005
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.