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arXiv · 2508.20994

GW emission and relativistic dynamical friction in intermediate mass ratio inspirals

P. Di Cintio·G. Bertone·C. Chiari·T. K. Karydas·B. J. Kavanagh·M. Pasquato·A. A. Trani
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Abstract

We present a set of preliminary simulations of intermediate mass ratio inspirals (IMRIs) inside dark matter (DM) spikes accounting for post-Newtonian corrections the interaction between the two black holes up to the order 2.5 in $c^2$, as well as relativistic corrections to the dynamical friction (DF) force exerted by the DM distribution. We find that, incorporating relativity reduces of a factor $1/2$ the inspiral time, for equivalent initial orbital parameters, with respect to the purely classical estimates. Vice versa, neglecting the DF of the spike systematically yields longer inspiral times.

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P. Di Cintio, G. Bertone, C. Chiari, T. K. Karydas, B. J. Kavanagh, M. Pasquato, A. A. Trani. 2025-08-28. GW emission and relativistic dynamical friction in intermediate mass ratio inspirals. https://arxiv.org/abs/2508.20994

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