Regular Kerr-like spacetime to interpret the observations for black hole candidates
Abstract
In this study, we investigate the electromagnetic radiation emitted by astrophysical black holes within the framework of the regular Kerr-like BH spacetime model, which describes rotating black holes with suppression parameter. Our focus lies on examining black holes found in X-ray binary systems, specifically GRS 1915+105, GRO J1655-40, XTE J1550-564, A0620-00, H1743-322, and GRS 1124-683. Our results suggest that the regular Kerr-like BH spacetime adequately explains the radiative efficiency of these sources as determined through the continuum fitting method (CFM). It was demonstrated that increase of the suppression parameter increases the radiative efficiency of a black hole for the fixed spin but reduces the maximum value it can take for bigger spins of black hole. Furthermore, utilizing the Blandford–Znajek mechanism, we illustrate the capability to reproduce the observed jet power. By integrating the outcomes of both analyses for the selected black hole systems, we establish more stringent constraints on the parameters of the spacetime model. The analysis indicates that this spacetime can successfully explain the observed radiative efficiency and jet power of A0620-00, H1743-322, GRO J1655-40, and XTE J1550-564. However, for GRS1124-683, the behavior shifts significantly with changes in the Lorentz factor. In the case of GRS1915+105, the results reveal non-overlapping regions for the two observed quantities, suggesting that the chosen spacetime is inadequate for reproducing both radiative efficiency and jet power simultaneously. • The increase of the suppression parameter increases the radiative efficiency. • We illustrated the capability to reproduce the observed jet power. • We establish more stringent constraints on the parameters of the spacetime model. • Results explain the observed radiative efficiency and jet power of known sources.