Selection Rule for Enhanced Dark Matter Annihilation
High Energy Physics - Phenomenology
2017-06-30 v3 Cosmology and Nongalactic Astrophysics
High Energy Astrophysical Phenomena
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.
Cite
@article{arxiv.1611.04606,
title = {Selection Rule for Enhanced Dark Matter Annihilation},
author = {Anirban Das and Basudeb Dasgupta},
journal= {arXiv preprint arXiv:1611.04606},
year = {2017}
}
Comments
7 pages, 3 figures; improved Sec.3, matches PRL version