Standard and non-standard primordial neutrinos
نویسنده
چکیده
The standard cosmological model predicts the existence of a cosmic neutrino background (CνB) with a present density of about nν + nν̄ ≃ 110 cm per flavour, which affects big-bang nucleosynthesis (BBN), cosmic microwave background (CMB) anisotropies, and the evolution of large scale structures (LSS). We report on a precision calculation of the CνB properties including the modification introduced by neutrino oscillations. The role of a possible neutrino-antineutrino asymmetry and the impact of non-standard neutrino-electron interactions on the CνB are also briefly discussed. PACS numbers: 14.60.Lm, 98.80.-k
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