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arXiv · 1011.6374

Cores in Dwarf Galaxies from Dark Matter with a Yukawa Potential

Abraham Loeb·Neal Weiner
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Abstract

We show that cold dark matter particles interacting through a Yukawa potential could naturally explain the recently observed cores in dwarf galaxies without affecting the dynamics of objects with a much larger velocity dispersion, such as clusters of galaxies. The velocity dependence of the associated cross-section as well as the possible exothermic nature of the interaction alleviates earlier concerns about strongly interacting dark matter. Dark matter evaporation in low-mass objects might explain the observed deficit of satellite galaxies in the Milky Way halo and have important implications for the first galaxies and reionization.

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Abraham Loeb, Neal Weiner. 2010-11-29. Cores in Dwarf Galaxies from Dark Matter with a Yukawa Potential. https://doi.org/10.1103/physrevlett.106.171302

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