The role of the reflection fraction in constraining black hole spin
Dauser T, Garcia J, Parker ML, Fabian AC, Wilms J (2014)
Publication Status: Published
Publication Type: Journal article
Publication year: 2014
Journal
Publisher: OXFORD UNIV PRESS
Book Volume: 444
Pages Range: L100-L104
Journal Issue: 1
Abstract
In many active galaxies, the X-ray reflection features from the innermost regions of the accretion disc are relativistically distorted. This distortion allows us to measure parameters of the black hole such as its spin. The ratio in flux between the direct and the reflected radiation, the so-called reflection fraction, is determined directly from the geometry and location of primary source of radiation. We calculate the reflection fraction in the lamp post geometry in order to determine its maximal possible value for a given value of black hole spin. We show that high reflection fractions in excess of two are only possible for rapidly rotating black holes, suggesting that the high spin sources produce the strongest relativistic reflection features. Using simulations we show that taking this constraint into account does significantly improve the determination of the spin values. We make software routines for the most popular X-ray data analysis packages available that incorporate these additional constraints.
Authors with CRIS profile
Thomas Dauser
Dr.Karl-Remeis-Sternwarte Bamberg, Astronomisches Institut
Jörn Wilms
Professur für Astronomie und Astrophysik
Involved external institutions
United Kingdom (GB)
United States (USA) (US)How to cite
APA:
Dauser, T., Garcia, J., Parker, M.L., Fabian, A.C., & Wilms, J. (2014). The role of the reflection fraction in constraining black hole spin. Monthly Notices of the Royal Astronomical Society, 444(1), L100-L104. https://doi.org/10.1093/mnrasl/slu125
MLA:
Dauser, Thomas, et al. "The role of the reflection fraction in constraining black hole spin." Monthly Notices of the Royal Astronomical Society 444.1 (2014): L100-L104.
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