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arXiv · 1909.12848

Transition from inspiral to plunge into a highly spinning black hole

Geoffrey Compère·Kwinten Fransen·Caroline Jonas
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Abstract

We extend the Ori-Thorne-Kesden procedure to consistently describe the non-quasi-circular transition around the ISCO from inspiral to plunge into a black hole of arbitrary spin, including near-extremal. We identify that for moderate or high spins the transition is governed by the Painlev\'e transcendent equation of the first kind while for extremely high spins it is governed by a self-similar solution to the Korteweg-de Vries equation. We match the transition solution at leading order in the high spin limit with the analytical quasi-circular inspiral in the near-horizon region. We also show that the central black hole of an extreme mass ratio binary has a near-extremality parameter that scales at least as the mass ratio due to superradiant gravitational wave emission, which excludes extremely high spins.

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Geoffrey Compère, Kwinten Fransen, Caroline Jonas. 2019-09-27. Transition from inspiral to plunge into a highly spinning black hole. https://doi.org/10.1088/1361-6382%2Fab79d3

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