2001/04/30 by Stefan Hofmann, Dominik J. Schwarz, Horst Stoecker · 1 citation
Physics and Astronomy · #astro-ph #hep-ph
paper · pdf · doi:10.1103/physrevd.64.083507
published as Phys.Rev.D64:083507,2001 · 13 pages, 5 figures; typos corrected; accepted by Physical Review D
arxiv created 2001/08/29 · arxiv updated 2009/11/30
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 about 30 MeV (for typical neutralino and sfermion masses) and free streaming after last scattering of neutralinos. The last scattering temperature is lower than the kinetic decoupling temperature by one order of magnitude. 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 to have masses above 10^(-7) solar masses.