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arXiv · hep-ph/0507325

Electroweak Baryogenesis, Large Yukawas and Dark Matter

Abstract

It has been recently shown that the electroweak baryogenesis mechanism is feasible in Standard Model extensions containing extra fermions with large Yukawa couplings. We show here that the lightest of these fermionic fields can naturally be a good candidate for cold dark matter. We find regions in the parameter space where the thermal relic abundance of this particle is compatible with the dark matter density of the Universe as determined by the WMAP experiment. We study direct and indirect dark matter detection for this model and compare with current experimental limits and prospects for upcoming experiments. We find, contrary to the standard lore, that indirect detection searches are more promising than direct detection ones, and they already exclude a portion of the parameter space.

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A. Provenza, M. Quiros, P. Ullio. 2005-07-28. Electroweak Baryogenesis, Large Yukawas and Dark Matter. https://doi.org/10.1088/1126-6708%2F2005%2F10%2F048

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