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What mass are the smallest protohalos?

Stefano Profumo·Kris Sigurdson·Marc Kamionkowski
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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.

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Stefano Profumo, Kris Sigurdson, Marc Kamionkowski. 2006-03-14. What mass are the smallest protohalos?. https://doi.org/10.1103/physrevlett.97.031301

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