What mass are the smallest protohalos?
Abstract
We calculate the kinetic-decoupling temperature for weakly interacting massive particles (WIMPs) in supersymmetric (SUSY) and universal-extra-dimension (UED) models that can account for the cold-dark-matter abundance determined from cosmic microwave background measurements. Depending on the parameters of the particle-physics model, a wide variety of decoupling temperatures is possible, ranging from several MeV to a few GeV. These decoupling temperatures imply a range of masses for the smallest protohalos much larger than previously thought -- ranging from 10^{-6} earth masses to 10^{2} earth masses. We expect the range of protohalos masses derived here to be characteristic of most particle-physics models that can thermally accommodate the required relic abundance of WIMP dark matter, even beyond SUSY and UED.
Keywords
Cite
@article{arxiv.astro-ph/0603373,
title = {What mass are the smallest protohalos?},
author = {Stefano Profumo and Kris Sigurdson and Marc Kamionkowski},
journal= {arXiv preprint arXiv:astro-ph/0603373},
year = {2007}
}
Comments
5 pages, 4 figures, submitted to Phys. Rev. Lett