Quasiperiodic oscillations from noncommutative inspired black holes

Abstract

We investigate the dynamics of test particles in the spacetime of noncommutative inspired black holes (NCi BHs). In this context, we first analyse spacetime properties of the NCi BHs together with innermost stable circular orbits (ISCOs) for the particles. It is observed that whereas the ISCO radius does not depend on the NC parameter, the frequencies of the Keplerian orbits and harmonic oscillations are NC parameter dependent. As an application, we consider quasiperiodic oscillations (QPOs) to test effects of the NC gravity around the BHs using twin-peak QPOs frequencies. It is found that the frequency changes even in the presence of the critical NC parameter are smaller than the error in the frequency measurements. The method developed for testing gravity using data from twin peak QPOs may also be applied to other alternate theories of gravity to obtain restrictions on the central BH parameters. We show that the orbits of QPOs lie near ISCO. This assumption may be helpful in solving the ISCO measurement problems in astrophysical observations. In addition, we determine the mass of the central BH in microquasar GRS 1915-105 and the QPO orbit in both the relativistic precession and warped disk models. It is shown that these parameters do not depend on the quantum corrections in the NC gravity. Lastly, we investigate the gravitational capture cross-section for photons and show that the effect of the NC parameter is also less than the error in shadow measurements of the supermassive BH (SMBH) Messier 87 (M87).