Constraints on charged black hole parameters using quasiperiodic oscillations data

Abstract

Testing gravity theories and constraining their parameters using data from astrophysical observations of quasiperiodic oscillations (QPOs) is a powerful approach to study the features of black holes (BHs) and gravity theories in the strong field regime. To this end, we investigate the dynamics of the test particles in the vicinity of some charged BHs such as Reissner–Nordström (RN), regular Bardeen and Ayon–Beato–Garcia (ABG). In particular, we calculate harmonic oscillations and the innermost stable circular orbits (ISCOs) of test particles around these BHs. As an astrophysical application, we discuss the twin peak QPOs in relativistic precession (RP) model and give the possible values of the upper and lower frequencies of the QPOs at the distance from ISCO to infinity around the extremely charged BHs. Moreover, we also investigate the position of the orbit, where twin peak QPO may take place around central (charged) BH in the microquasar GRS 1915-105. We also study the dependence of the distance between the QPO position and ISCO from the BH charge. Using the upper and lower frequencies of the QPO, we obtain the relationship between the mass and charge of the central BH in the microquasar. Finally, we compare the effects of the spin of the Kerr BH and BH charges on the QPO in microquasar GRS 1915-105. We find that the BH charge can mimic the spin up to [Formula: see text] in the Bardeen model and up to [Formula: see text] in the case of special regular BH, admitting the same QPO frequencies.