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arXiv · 1101.5413

Semi-annihilation of Dark Matter

Francesco D'Eramo
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Abstract

The semi-annihilation reaction takes the schematic form psi_i psi_j -> psi_k phi, where psi_i are stable dark matter particles and phi is an unstable state. Such reactions are allowed when dark matter is stabilized by a larger symmetry than just Z_2. They lead to non-trivial dark matter dynamics in the early universe, and the thermal production of the relic particles can be completely controlled by semi-annihilations. This process might also take place today in the Milky Way, enriching the (semi-)annihilation final state spectrum observed in indirect detection experiments.

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Francesco D'Eramo. 2011-01-27. Semi-annihilation of Dark Matter. https://arxiv.org/abs/1101.5413

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