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arXiv · 2009.06705

Shadows of rotating Hayward-de Sitter black holes with astrometric observables

Peng-Zhang He·Qi-Qi Fan·Hao-Ran Zhang·Jian-Bo Deng
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Abstract

Motivated by recent work on rotating black hole shadow [Phys. Rev. D101, 084029 (2020)], we investigate the shadow behaviors of rotating Hayward-de Sitter black hole for static observers at a finite distance in terms of astronomical observables. This paper uses the newly introduced distortion parameter in [arXiv:2006.00685] to describe the shadow's shape quantitatively. We show that the spin parameter would distort shadows and the magnetic monopole charge would increase the degree of deformation. At the same time, the distortion could be relieved because of the cosmological constant and the distortion would increase with the distance from the black hole. Besides, the spin parameter, magnetic monopole charge and cosmological constant increase will cause the shadow to shrink.

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Peng-Zhang He, Qi-Qi Fan, Hao-Ran Zhang, Jian-Bo Deng. 2020-09-08. Shadows of rotating Hayward-de Sitter black holes with astrometric observables. https://doi.org/10.1140/epjc/s10052-020-08707-z

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