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arXiv · 2004.02654

Extreme mass ratio inspirals with spinning secondary: a detailed study of equatorial circular motion

Gabriel Andres Piovano·Andrea Maselli·Paolo Pani
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Abstract

Extreme mass-ratio inspirals detectable by the future Laser Interferometer Space Antenna provide a unique way to test general relativity and fundamental physics. Motivated by this possibility, here we study in detail the EMRI dynamics in the presence of a spinning secondary, collecting and extending various results that appeared in previous work and also providing useful intermediate steps and new relations for the first time. We present the results of a frequency-domain code that computes gravitational-wave fluxes and the adiabatic orbital evolution for the case of circular, equatorial orbits with (anti)aligned spins. The spin of the secondary starts affecting the gravitational-wave phase at the same post-adiabatic order as the leading-order self-force terms and introduces a detectable dephasing, which can be used to measure it at $5-25\%$ level, depending on individual spins. In a companion paper we discuss the implication of this effect for tests of the Kerr bound.

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Gabriel Andres Piovano, Andrea Maselli, Paolo Pani. 2020-06-11. Extreme mass ratio inspirals with spinning secondary: a detailed study of equatorial circular motion. https://doi.org/10.1103/physrevd.102.024041

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