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arXiv · 1806.11539

Towards an improved model of self-interacting dark matter haloes

Anastasia Sokolenko·Kyrylo Bondarenko·Thejs Brinckmann·Jesús Zavala·Mark Vogelsberger·Torsten Bringmann·Alexey Boyarsky
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Abstract

In this work, we discuss the relation between the strength of the self-interaction of dark matter particles and the predicted properties of the inner density distributions of dark matter haloes. We present the results of $N$-body simulations for 28 haloes performed with the same initial conditions for cold dark matter and for self-interacting dark matter, for a range of cross-sections. We provide a simple phenomenological description of these results and compare with the semi-analytical model typically used in the literature. Using these results, we then predict how the inner dark matter surface density and core radius should depend on the self-interaction cross-section for observed haloes.

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Anastasia Sokolenko, Kyrylo Bondarenko, Thejs Brinckmann, Jesús Zavala, Mark Vogelsberger, Torsten Bringmann, Alexey Boyarsky. 2019-01-30. Towards an improved model of self-interacting dark matter haloes. https://doi.org/10.1088/1475-7516%2F2018%2F12%2F038

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