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arXiv · 2609.20185

Radiative losses from unbound orbits at quadratic order in spin from MPM formalism

Donato Bini·Giorgio Di Russo
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Abstract

We study the spinning two-body system in the aligned spin case for hyperboliclike motions computing all radiative losses (at the 2PN absolute accuracy and including spin-squared corrections) using the MPM formalism and generalizing previous results valid at linear order in spin [Phys. Rev. D \textbf{108}, no.6, 064049 (2023)]. Leading PM order results are checked against existing literature, whereas higher-order PM results (within the 2PN accuracy) are new with this work. As a by-product of our general results we analyze the spinning situation which supports radial fall (at 2PN and including spin-squared accuracy level contributions), showing that as soon as the PN accuracy increases deviations from radial fall appear necessarily.

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Donato Bini, Giorgio Di Russo. 2026-07-24. Radiative losses from unbound orbits at quadratic order in spin from MPM formalism. https://arxiv.org/abs/2609.20185

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