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arXiv · hep-ph/0308173

Spontaneous baryogenesis in flat directions

Fuminobu Takahashi·Masahide Yamaguchi
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Abstract

We discuss a spontaneous baryogenesis mechanism in flat directions. After identifying the Nambu-Goldstone mode which derivatively couples to the associated $U$(1) current and rotates due to the A-term, we show that spontaneous baryogenesis can be naturally realized in the context of the flat direction. As applications, we discuss two scenarios of baryogenesis in detail. One is baryogenesis in a flat direction with a vanishing $B-L$ charge, especially, with neither baryon nor lepton charge, which was recently proposed by Chiba and the present authors. The other is a baryogenesis scenario compatible with a large lepton asymmetry.

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Fuminobu Takahashi, Masahide Yamaguchi. 2004-04-03. Spontaneous baryogenesis in flat directions. https://doi.org/10.1103/physrevd.69.083506

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