Deciphering signatures of Bardeen black holes from the observed quasi-periodic oscillations

Abstract Quasi-periodic oscillations (QPOs) observed in the power spectrum of black holes are unique observational probes to background spacetime since they can be directly related timescales associated with motion matter orbiting vicinity hole horizon. In this regard, high frequency QPOs (HFQPOs) particularly interesting as occur commensurable pairs, most common ratio being 3:2 twin peak QPOs. The theoretical models which aim explain these express frequencies terms epicyclic test particles a given spacetime. work, we study signatures Bardeen from spectrum. rotating, regular magnetic monopole charge. Such backgrounds theoretically potentially evade curvature singularity, otherwise unavoidable general relativistic holes. We perform χ 2 analysis by comparing available observations quasi-periodic sources relevant and note that Kerr relativity observationally more favored compared Our reveals very charges disfavored QPO observations.