Eccentric equatorial trajectories around a Kerr black hole as a QPO model for M82X-1

Prerna Rana, A. Mangalam

Published 2022-07-12Version 1

We study the bound orbit conditions for equatorial and eccentric orbits around a Kerr black hole both in the parameter space ($E$, $L$, $a$) representing the energy, angular momentum of the test particle, and spin of the black hole, and also ($e$, $\mu$, $a$) space representing the eccentricity, inverse-latus rectum of the orbit, and spin. We apply these conditions and implement the relativistic precession (RP) model to M82X-1, which is an Intermediate-mass black hole (IMBH) system, where two high-frequency Quasi-Periodic Oscillations (HFQPOs) and a low-frequency QPO were simultaneously observed. Assuming that the QPO frequencies can also be generated by equatorial and eccentric trajectories, we calculate the probability distributions to infer $e$, $a$, and periastron distance, $r_p$, of the orbit giving rise to simultaneous QPOs. We find that an eccentric orbit solution is possible in the region between innermost stable circular orbit (ISCO) and the marginally bound circular orbit (MBCO) for $e=0.2768^{+0.0657}_{-0.0451}$, $a=0.2897 \pm 0.0087$, and $r_p=4.6164^{+0.0694}_{-0.1259}$.