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arXiv · 1403.5234

Photon Regions and Shadows of Kerr-Newman-NUT Black Holes with a Cosmological Constant

Arne Grenzebach·Volker Perlick·Claus Lämmerzahl
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Abstract

We consider the Plebański class of electrovacuum solutions to the Einstein equations with a cosmological constant. These space-times, which are also known as the Kerr-Newman-NUT-(anti-)de Sitter space-times, are characterized by a mass $m$, a spin $a$, a parameter $β$ that comprises electric and magnetic charge, a NUT parameter $\ell$ and a cosmological constant $Λ$. Based on a detailed discussion of the photon regions in these space-times (i.e., of the regions in which spherical lightlike geodesics exist), we derive an analytical formula for the shadow of a Kerr-Newman-NUT-(anti-)de Sitter black hole, for an observer at given Boyer-Lindquist coordinates $(r_O, \vartheta_O)$ in the domain of outer communication. We visualize the photon regions and the shadows for various values of the parameters.

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Arne Grenzebach, Volker Perlick, Claus Lämmerzahl. 2014-06-17. Photon Regions and Shadows of Kerr-Newman-NUT Black Holes with a Cosmological Constant. https://doi.org/10.1103/physrevd.89.124004

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