Sgr A* Shadow Study with KTN Space Time and Investigation of NUT Charge Existence

Abstract

In this paper, I investigate the existence of the NUT charge through the KTN spacetime using shadow observations of Sgr A*. I report that the range of my constraint for the NUT charge is between $-$0.5 and 0.5 for Schwarzschild-like and very slowly rotating KTN black holes. This range extends to 1.5 for spins up to $-$2 and $-$1.5 for spins up to 2 based on Keck observations for both 40${}^{\circ }$ and 10${}^{\circ }$ viewing angles. For VLTI observations, Schwarzschild-like and very slowly rotating KTN black holes are excluded for a 40${}^{\circ }$ viewing angle, and the NUT charge is constrained to a very narrow range for a 10${}^{\circ }$ viewing angle. I report that the possibility of having KTN naked singularities in Sgr A* is small, considering the uncertainties in the shadow size.

Published in Universe

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Cited by in corpus (2)

• Modelling the Sgr A${}^{\ast }$ and M87${}^{\ast }$ shadows by using the Kerr-Taub-NUT metrics in the presence of a scalar field
• Shadows for Kerr-Sen-Taub-NUT black holes with Manko-Ruiz parameter