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arXiv · 1507.07441

Dynamics of extended bodies in a Kerr spacetime with spin-induced quadrupole tensor

Donato Bini·Guillaume Faye·Andrea Geralico
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Abstract

The features of equatorial motion of an extended body in Kerr spacetime are investigated in the framework of the Mathisson-Papapetrou-Dixon model. The body is assumed to stay at quasi-equilibrium and respond instantly to external perturbations. Besides the mass, it is completely determined by its spin, the multipolar expansion being truncated at the quadrupole order, with a spin-induced quadrupole tensor. The study of the radial effective potential allows to analytically determine the ISCO shift due to spin and the associated frequency of the last circular orbit.

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Donato Bini, Guillaume Faye, Andrea Geralico. 2015-07-27. Dynamics of extended bodies in a Kerr spacetime with spin-induced quadrupole tensor. https://arxiv.org/abs/1507.07441

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