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arXiv · 1601.00838

Testing the Kerr nature of black hole candidates using iron line reverberation mapping in the CPR framework

Jiachen Jiang·Cosimo Bambi·James F. Steiner
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Abstract

The iron K$\alpha$ line commonly observed in the X-ray spectrum of black hole candidates is produced by X-ray fluorescence of the inner accretion disk. This line can potentially be quite a powerful tool to probe the spacetime geometry around these objects and test the Kerr black hole hypothesis. In a previous paper, we studied the ability to constrain possible deviations from the Kerr solution from the standard time-integrated iron line spectrum within the Cardoso-Pani-Rico framework. In the present work, we expand on that study and consider iron line reverberation mapping in the CPR framework. That is, we consider the time-evolution of the iron line profile in response to fluctuations in the X-ray primary source. Our simulations clearly show that the time information in reverberation mapping can better constrain the background metric than the time-integrated approach, and this is true, notably, for the deformation parameter $\epsilon^r_3$, which is only weakly informed by a time-integrated observation.

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Jiachen Jiang, Cosimo Bambi, James F. Steiner. 2016-01-05. Testing the Kerr nature of black hole candidates using iron line reverberation mapping in the CPR framework. https://doi.org/10.1103/physrevd.93.123008

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