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arXiv · hep-ph/0510079

Dark Matter and the Baryon Asymmetry

Glennys R. Farrar·Gabrijela Zaharijas
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Abstract

We present a mechanism to generate the baryon asymmetry of the Universe which preserves the net baryon number created in the Big Bang. If dark matter particles carry baryon number $B_X$, and $σ^{\rm annih}_{\bar{X}} < σ^{\rm annih}_{X} $, the $\bar{X}$'s freeze out at a higher temperature and have a larger relic density than $X$'s. If $m_X \lsi 4.5 B_X $GeV and the annihilation cross sections differ by $\mathcal{O}$(10%) or more, this type of scenario naturally explains the observed $Ω_{DM} \approx 5 Ω_b$. Two concrete examples are given, one of which can be excluded on observational grounds.

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Glennys R. Farrar, Gabrijela Zaharijas. 2005-10-06. Dark Matter and the Baryon Asymmetry. https://doi.org/10.1103/physrevlett.96.041302

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