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arXiv · 1804.06070

Off-equatorial stable circular orbits for spinning particles

Sajal Mukherjee·Rajesh Kumble Nayak
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Abstract

In this article, we investigate the motion of a spinning particle at a constant inclination, different from the equatorial plane, around a Kerr black hole. We mainly explore the possibilities of stable circular orbits for different spin supplementary conditions. The Mathission-Papapetrau's equations are extensively applied and solved within the framework of linear spin approximation. We explicitly show that for a given spin vector of the form $S^{a} = \left(0,S^r,S^θ,0\right)$ , there exists an unique circular orbit at $(r_c,θ_c)$ defined by the simultaneous minima of energy, angular momentum and Carter constant. This corresponds to the Innermost Stable Circular Orbit (ISCO) which is located on a non-equatorial plane. We further establish that the location ($r_c,θ_c$) of the ISCO for a given spinning particle depends on the radial component of the spin vector ($S^r$) as well as the angular momentum of the black hole ($J$). The implications of using different spin supplementary conditions are investigated.

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Sajal Mukherjee, Rajesh Kumble Nayak. 2018-09-20. Off-equatorial stable circular orbits for spinning particles. https://doi.org/10.1103/physrevd.98.084023

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