Cosmological constraints on dark matter models with velocity-dependent annihilation cross section
arXiv:1102.4658 · doi:10.1103/PhysRevD.83.123511
Abstract
We derive cosmological constraints on the annihilation cross section of dark matter with velocity-dependent structure, motivated by annihilating dark matter models through Sommerfeld or Breit-Wigner enhancement mechanisms. In models with annihilation cross section increasing with decreasing dark matter velocity, big-bang nucleosynthesis and cosmic microwave background give stringent constraints.
23 pages, 9 figures; Added references