Public Release of RELXILL_NK: A Relativistic Reflection Model for Testing Einstein's Gravity

Abstract

We present the public release version of relxill_nk, an X-ray reflection model for testing the Kerr hypothesis and general relativity. This model extends the relxill model that assumes the black hole spacetime is described by the Kerr metric. We also present relxilllp_nk, the first non-Kerr X-ray reflection model with a lamppost corona configuration, as well as all other models available in the full relxill_nk package. In all models the relevant relativistic effects are calculated through a general relativistic ray-tracing code that can be applied to any well-behaved, stationary, axisymmetric, and asymptotically flat black hole spacetime. We show that the numerical error introduced by using a ray-tracing code is not significant as compared with the observational error present in current X-ray reflection spectrum observations. In addition, we present the reflection spectrum for the Johannsen metric as calculated by relxill_nk.

15 pages, 8 figures. v2: refereed version. Code and documentation available at http://www.physics.fudan.edu.cn/tps/people/bambi/Site/RELXILL_NK.html and at http://www.tat.physik.uni-tuebingen.de/~nampalliwar/relxill_nk/

References in corpus (3)

• The role of the reflection fraction in constraining black hole spin
• Bumpy Black Holes in Alternate Theories of Gravity
• Constraints on the spacetime metric around seven "bare" AGNs using X-ray reflection spectroscopy

Cited by in corpus (4)

• Modeling uncertainties in X-ray reflection spectroscopy measurements II: Impact of the radiation from the plunging region
• X-ray reflection spectroscopy with Kaluza-Klein black holes
• Modeling uncertainties in X-ray reflection spectroscopy measurements I: Impact of higher order disk images
• Reflection features in the X-ray spectrum of Fairall 9 and implications for tests of general relativity