Quasiperiodic oscillations for spherically symmetric regular black holes
Abstract
We consider the recent datasets of quasiperiodic oscillations from eight different low mass x-ray binaries. We here interpret their physical features in the context of given regular black hole solutions and verify their applicability to neutron stars. We evaluate the numerical constraints over the free parameters of Bardeen, Hayward, and Dymnikova regular solutions by performing a set of Markov chain Monte Carlo analyses, based on the Metropolis algorithm. For each source, we evaluate the best-fit parameters, among which the mass and the regularization scale or parameter, compare and contrast them with the current literature. We also infer the corresponding innermost stable circular orbit radii and the radial extents of the accretion disks. Focusing on how to identify discrepancies among theoretical models and observations, our results show that, in most of the cases, regular black holes, in particular the Bardeen and Hayward spacetimes are slightly more suitable to describe neutron stars than the Schwarzschild geometry, whereas the Dymnikova metric is ruled out.