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arXiv · 2110.11704

Study of circular geodesics and shadow of rotating charged black hole surrounded by perfect fluid dark matter immersed in plasma

Anish Das·Ashis Saha·Sunandan Gangopadhyay
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Abstract

In this work, we consider a rotating charged black hole surrounded by perfect fluid dark matter. We consider the system to be immersed in non-magnetised, pressureless plasma. First, we evaluate the null geodesics in order to study the co-rotating and counter rotating photon orbits. Further, we analyse the null geodesics to calculate the celestial coordinates ($\alpha, \beta$). The celestial coordinates are used to determine the black hole shadow radius ($R_s$). Thereafter, we observe and analyse the effects of black hole spacetime, perfect fluid dark matter and plasma parameters ($a$, $Q$, $\chi$, $k$) on the black hole shadow in detail. Finally, we study the effect of plasma distribution on the effective potential ($V_{eff}$) of the black hole spacetime as encountered by the photons. We also present bounds on the plasma parameter from the observational data from $M87^{*}$ central supermassive black hole.

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Anish Das, Ashis Saha, Sunandan Gangopadhyay. 2021-10-22. Study of circular geodesics and shadow of rotating charged black hole surrounded by perfect fluid dark matter immersed in plasma. https://doi.org/10.1088/1361-6382%2Fac50ed

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