Neutrino degeneracy effect on neutrino oscillations and primordial helium yield Original Research Article

In this work we present the results of our numerical analysis of the effect of lepton asymmetries L on neutrino oscillations and consequently on helium production in a model of cosmological nucleosynthesis with active-sterile neutrino oscillations. We performed detailed calculations of the neutron-proton ratio till its freezing and the subsequent synthesis of helium-4 for a wide range of values of the initial lepton asymmetry 10−4−10−10 and for the complete set of mixing parameters of the oscillation model described by Kirilova and Chizhov [1]: δm2 ⩽ 10−7 eV2 and any ϑ.