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arXiv · 1610.08791

Constraining the Kerr parameters via X-ray reflection spectroscopy

M. Ghasemi-Nodehi·Cosimo Bambi
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Abstract

In a recent paper [Ghasemi-Nodehi & Bambi, EPJC 76 (2016) 290], we have proposed a new parametrization for testing the Kerr nature of astrophysical black hole candidates. In the present work, we study the possibility of constraining the "Kerr parameters" of our proposal using X-ray reflection spectroscopy, the so-called iron line method. We simulate observations with the LAD instrument on board of the future eXTP mission assuming an exposure time of 200~ks. We fit the simulated data to see if the Kerr parameters can be constrained. If we have the correct astrophysical model, 200~ks observations with LAD/eXTP can constrain all the Kerr parameters with the exception of $b_{11}$, whose impact on the iron line profile is extremely weak and its measurement looks very challenging.

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BibTeXRIS

M. Ghasemi-Nodehi, Cosimo Bambi. 2016-10-27. Constraining the Kerr parameters via X-ray reflection spectroscopy. https://doi.org/10.1103/physrevd.94.104062

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