1307.4698 (Chandrachur Chakraborty)

ISCOs in Kerr-Taub-NUT and Taub-NUT spacetimes    [PDF]

Chandrachur Chakraborty

We study the null and timelike geodesics of the Kerr-Taub-NUT spacetimes in the equatorial plane. We also study the null and timelike geodesics of Taub-NUT and massless Taub-NUT spacetime as the special cases of Kerr-Taub-NUT spacetimes. We calculate the radii of the direct ISCOs for the various cases of the above mentioned spacetimes. We show that the ISCO coincides with the horizon in extremal KTN spacetime for both null and timelike geodesics. We also show that in Taub-NUT spacetime, the radius of the direct ISCO increases with the increasing of NUT charge and there is no any stable circular orbit in massless NUT spacetimes for timelike geodesics.

View original: http://arxiv.org/abs/1307.4698