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Damping of inhomogeneities in neutralino dark matter

Dominik J. Schwarz·Stefan Hofmann·Horst Stoecker
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Abstract

The lightest supersymmetric particle, most likely the neutralino, might account for a large fraction of dark matter in the Universe. We show that the primordial spectrum of density fluctuations in neutralino cold dark matter (CDM) has a sharp cut-off due to two damping mechanisms: collisional damping during the kinetic decoupling of the neutralinos at O(10 MeV) and free streaming after last scattering of neutralinos. The cut-off in the primordial spectrum defines a minimal mass for CDM objects in hierarchical structure formation. For typical neutralino and sfermion masses the first gravitationally bound neutralino clouds have masses above 10^(-6) M_\odot.

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Dominik J. Schwarz, Stefan Hofmann, Horst Stoecker. 2001-10-29. Damping of inhomogeneities in neutralino dark matter. https://arxiv.org/abs/astro-ph/0110601

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