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arXiv · 1510.02179

Semi-Annihilating Wino-Like Dark Matter

Andrew P. Spray·Yi Cai
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Abstract

Semi-annihilation is a generic feature of dark matter theories with symmetries larger than Z_2. We explore a model based on a Z_4-symmetric dark sector comprised of a scalar singlet and a "wino"-like fermion SU(2)_L triplet. This is the minimal example of semi-annihilation with a gauge-charged fermion. We study the interplay of the Sommerfeld effect in both annihilation and semi-annihilation channels. The modifications to the relic density allow otherwise-forbidden regions of parameter space and can substantially weaken indirect detection constraints. We perform a parameter scan and find that the entire region where the model comprises all the observed dark matter is accessible to current and planned direct and indirect searches.

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Andrew P. Spray, Yi Cai. 2015-10-08. Semi-Annihilating Wino-Like Dark Matter. https://arxiv.org/abs/1510.02179

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