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

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° and 10° viewing angles. For VLTI observations, Schwarzschild-like and very slowly rotating KTN black holes are excluded for a 40° viewing angle, and the NUT charge is constrained to a very narrow range for a 10° viewing angle. I report that the possibility of having KTN naked singularities in Sgr A* is small, considering the uncertainties in the shadow size.