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Transformation-Induced Nonthermal Neutrino Spectra and Primordial Nucleosynthesis

Kevork Abazajian·Xiangdong Shi·George M. Fuller
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Abstract

We examine in detail the changes in the production of primordial helium resulting from nonthermal neutrino momentum distributions produced by resonant transformation of electron-type neutrinos to steriles. These transformations, anti-nu_e -> anti-nu_s (nu_e->nu_s), amplify a positive (negative) lepton number asymmetry. We find that the resulting supression relative to a thermal distribution of low energy nu_e reduces n -> p conversion to a greater extent than does the enhancement of n -> p from an identical suppression of anti-nu_e. Thus, equal lepton-number asymmetries of opposite sign have unequal effects on the resulting helium yield in primordial nucleosynthesis.

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Kevork Abazajian, Xiangdong Shi, George M. Fuller. 1999-09-17. Transformation-Induced Nonthermal Neutrino Spectra and Primordial Nucleosynthesis. https://arxiv.org/abs/astro-ph/9909320

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