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Innermost Stable Circular Orbit of a Spinning Particle in Kerr Spacetime

Shingo Suzuki·Kei-ichi Maeda
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Abstract

We study stability of a circular orbit of a spinning test particle in a Kerr spacetime. We find that some of the circular orbits become unstable in the direction perpendicular to the equatorial plane, although the orbits are still stable in the radial direction. Then for the large spin case ($S < \sim O(1)), the innermost stable circular orbit (ISCO) appears before the minimum of the effective potential in the equatorial plane disappears. This changes the radius of ISCO and then the frequency of the last circular orbit.

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Shingo Suzuki, Kei-ichi Maeda. 1997-12-26. Innermost Stable Circular Orbit of a Spinning Particle in Kerr Spacetime. https://doi.org/10.1103/physrevd.58.023005

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