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arXiv · 2306.11558

Extended bodies with spin induced quadrupoles on circular equatorial orbits in Kerr spacetime

Iason Timogiannis·Georgios Lukes-Gerakopoulos·Theocharis A. Apostolatos
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Abstract

This work discusses the motion of extended test bodies as described by the Mathisson-Papapetrou-Dixon (MPD) equations in the pole-dipole-quadrupole approximation. We focus on the case that the quadrupole is solely induced by the spin of the body which is assumed to move on a circular equatorial orbit in a Kerr background. To fix the center of mass of the MPD body we use two different spin supplementary conditions (SSCs): the Tulczyjew-Dixon SSC and the Mathisson-Pirani SSC. We provide the frequencies of the circular equatorial orbits for the pole-dipole-(spin induced) quadrupole approximation of the body for both SSCs. In the process we develop an explicit four-velocity four-momentum relation for a pole-dipole-quadrupole body under the Mathisson-Pirani SSC.

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Iason Timogiannis, Georgios Lukes-Gerakopoulos, Theocharis A. Apostolatos. 2023-06-20. Extended bodies with spin induced quadrupoles on circular equatorial orbits in Kerr spacetime. https://doi.org/10.1103/physrevd.108.084023

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