A Reflection Model with a Radial Disk Density Profile
Abstract
In this paper we present relxilldgrad_nk, a relativistic reflection model in which the electron density of the accretion disk is allowed to have a radial power-law profile. The ionization parameter also has a nonconstant radial profile and is calculated self-consistently from the electron density and the emissivity. We show the impact of the implementation of the electron density gradient in our model by analyzing a NuSTAR spectrum of the Galactic black hole in EXO 1846-031 during its last outburst in 2019 and a putative future observation of the same source with Athena and eXTP. For the NuSTAR spectrum, we find that the new model provides a better fit, but there is no significant difference in the estimation of the model parameters. For the Athena+eXTP simulation, we find that a model without a disk density profile is unsuitable to test the spacetime metric around the compact object in the sense that modeling uncertainties can incorrectly lead to finding a nonvanishing deformation from the Kerr solution.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 2021
- DOI:
- 10.3847/1538-4357/ac3237
- arXiv:
- arXiv:2108.00375
- Bibcode:
- 2021ApJ...923..175A
- Keywords:
-
- 98;
- 886;
- 14;
- 1810;
- 86;
- Astrophysics - High Energy Astrophysical Phenomena;
- General Relativity and Quantum Cosmology
- E-Print:
- 11 pages, 9 figures. v2: refereed version