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arXiv · 2504.06448

Analytic calculation of dynamical friction for Plummer sphere in ultralight dark matter

O. V. Barabash·T. V. Gorkavenko·V. M. Gorkavenko·O. M. Teslyk·N. S. Yakovenko·A. O. Zaporozhchenko·E. V. Gorbar
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Abstract

The dynamical friction force acting on a spatially extended probe (globular clusters and dwarf galaxies) moving in the environment of ultralight bosonic dark matter in the state of the Bose-Einstein condensate is determined. Modeling the probe as a Plumer sphere of radius $l_p$, the radial and tangential components of the dynamic friction force are found in an analytic form, which reduce in the limit $l_p \to 0$ to the corresponding analytic expressions obtained in the literature in the case of a point probe. The dependence of the dynamical friction force on boson particle mass $m$ was analyzed and found to be non-monotonous in the interval $10^{-23} - 10^{-21}$eV.

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O. V. Barabash, T. V. Gorkavenko, V. M. Gorkavenko, O. M. Teslyk, N. S. Yakovenko, A. O. Zaporozhchenko, E. V. Gorbar. 2025-04-08. Analytic calculation of dynamical friction for Plummer sphere in ultralight dark matter. https://doi.org/10.15407/ujpe70.11.759

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