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arXiv · 1102.4658

Cosmological constraints on dark matter models with velocity-dependent annihilation cross section

Junji Hisano·Masahiro Kawasaki·Kazunori Kohri·Takeo Moroi·Kazunori Nakayama·Toyokazu Sekiguchi
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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.

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Junji Hisano, Masahiro Kawasaki, Kazunori Kohri, Takeo Moroi, Kazunori Nakayama, Toyokazu Sekiguchi. 2011-03-20. Cosmological constraints on dark matter models with velocity-dependent annihilation cross section. https://doi.org/10.1103/physrevd.83.123511

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