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arXiv · 1611.04606

Selection Rule for Enhanced Dark Matter Annihilation

Anirban Das·Basudeb Dasgupta
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Abstract

We point out a selection rule for enhancement (suppression) of odd (even) partial waves of dark matter coannihilation or annihilation using Sommerfeld effect. Using this, the usually velocity-suppressed p-wave annihilation can dominate the annihilation signals in the present Universe. The selection mechanism is a manifestation of the exchange symmetry of identical incoming particles, and generic for multi-state DM with off-diagonal long-range interactions. As a consequence, the relic and late-time annihilation rates are parametrically different and a distinctive phenomenology, with large but strongly velocity-dependent annihilation rates, is predicted.

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Anirban Das, Basudeb Dasgupta. 2017-06-28. Selection Rule for Enhanced Dark Matter Annihilation. https://doi.org/10.1103/physrevlett.118.251101

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