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arXiv · 2010.00151

Shadow cast by a rotating and nonlinear magnetic-charged black hole in perfect fluid dark matter

Abstract

We derived an exact solution of the spherically symmetric Hayward black hole surrounded by perfect fluid dark matter (PFDM). By applying the Newman-Janis algorithm, we generalized it to the corresponding rotating black hole. Then, we studied the shadows of rotating Hayward black hole in PFDM. The apparent shape of the shadow depends upon the black hole spin $a$, the magnetic charge $Q$ and the PFDM intensity parameter $k$ ($k<0$). The shadow is a perfect circle in the non-rotating case ($a=0$) and a deformed one in the rotating case ($a\neq{0}$). For a fixed value of $a$, the size of the shadow increases with the increasing $\vert{k}\vert$, but decreases with the increasing $Q$. We further investigated the black hole emission rate. We found that the emission rate decreases with the increasing $\vert{k}\vert$ (or $Q$) and the peak of the emission shifts to lower frequency. Finally, we discussed the observational prospects corresponding to the supermassive black hole $\mathrm{Sgr\ A^{*}}$ at the center of the Milky Way.

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Tian-Chi Ma, He-Xu Zhang, Peng-Zhang He, Hao-Ran Zhang, Yuan Chen, Jian-Bo Deng. 2020-10-01. Shadow cast by a rotating and nonlinear magnetic-charged black hole in perfect fluid dark matter. https://doi.org/10.1142/s0217732321501121

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