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arXiv · 0808.3994

Changes in Dark Matter Properties After Freeze-Out

Timothy Cohen·David E. Morrissey·Aaron Pierce
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Abstract

The properties of the dark matter that determine its thermal relic abundance can be very different from the dark matter properties today. We investigate this possibility by coupling a dark matter sector to a scalar that undergoes a phase transition after the dark matter freezes out. If the value of Omega_DM h^2 calculated from parameters measured at colliders and by direct and indirect detection experiments does not match the astrophysically observed value, a novel cosmology of this type could provide the explanation. This mechanism also has the potential to account for the "boost factor" required to explain the PAMELA data.

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Timothy Cohen, David E. Morrissey, Aaron Pierce. 2008-12-16. Changes in Dark Matter Properties After Freeze-Out. https://doi.org/10.1103/physrevd.78.111701

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