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arXiv · 1208.3562

Dark Radiation in LARGE Volume Models

Michele Cicoli·Joseph P. Conlon·Fernando Quevedo
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Abstract

We consider reheating driven by volume modulus decays in the LARGE Volume Scenario. Such reheating always generates non-zero dark radiation through the decays to the axion partner, while the only competitive visible sector decays are Higgs pairs via the Giudice-Masiero term. In the framework of sequestered models where the cosmological moduli problem is absent, the simplest model with a shift-symmetric Higgs sector generates 1.56 < N_{eff} - N_{eff,SM} < 1.74. For more general cases, the known experimental bounds on N_{eff} strongly constrain the parameters and matter content of the models.

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Michele Cicoli, Joseph P. Conlon, Fernando Quevedo. 2012-09-21. Dark Radiation in LARGE Volume Models. https://doi.org/10.1103/physrevd.87.043520

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