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arXiv · 2112.05385

Quasar continuum spectrum disfavors black holes with a magnetic monopole charge

Indrani Banerjee·Vijay Shersingh Chawan·Bhaswati Mandal·Siddharth Kumar Sahoo·Soumitra SenGupta
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Abstract

Black holes carrying a magnetic monopole charge are a subject of interest for a long time. In this work we explore the possibility of an observational evidence of such black holes carrying a magnetic monopole, namely the Bardeen rotating black holes. We derive the theoretical spectrum from the accretion disk surrounding a Bardeen black hole using the thin-disk approximation. We compare the theoretically derived spectrum in comparison to the optical data of eighty Palomar Green quasars to constrain the monopole charge parameter $g$ and the spin parameter $a$ of the quasars. From our analysis we note that the Kerr-scenario in \gr\ is observationally more favored than black holes with a monopole charge. We arrive at such a conclusion using error estimators like $\chi^2$, the Nash-Sutcliffe efficiency, the index of agreement and their modified forms. In particular, black holes with $g \geq 0.03$ are outside $99\%$ confidence interval. The implications are discussed.

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Indrani Banerjee, Vijay Shersingh Chawan, Bhaswati Mandal, Siddharth Kumar Sahoo, Soumitra SenGupta. 2021-12-10. Quasar continuum spectrum disfavors black holes with a magnetic monopole charge. https://doi.org/10.1103/physrevd.105.064073

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