Related papers: Lepton asymmetry effect on neutrino oscillations a…
In this article we discuss lepton asymmetry effect on BBN with neutrino oscillations. We argue that asymmetry much smaller than 0.01, although not big enough to influence directly the nucleosynthesis kinetics, can effect considerably BBN…
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…
We discuss the interplay between lepton asymmetry L and neutrino oscillations in the early Universe. Neutrino oscillations may suppress or enhance previously existing L. On the other hand L is capable to suppress or enhance neutrino…
Oscillations between ordinary and sterile neutrinos can generate large neutrino asymmetries in the early universe. These asymmetries can significantly affect big bang nucleosynthesis (BBN) through modification of nuclear reaction rates. We…
The lepton asymmetry that could be generated in the early universe through oscillations of active to sterile neutrinos is calculated (almost) analytically for small mixing angles, sin 2\theta < 10^{-2}. It is shown that for a mass squared…
We study the nonresonant oscillations between left-handed electron neutrinos nu_e and nonthermalized sterile neutrinos nu_s in the early Universe plasma. The case when nu_s do not thermalize till 2 MeV and the oscillations become effective…
Lepton asymmetry generated in the early universe by neutrino oscillations into sterile partners is calculated. Kinetic equations are analytically reduced to a simple form that permits an easy numerical treatment. Asymptotic values of the…
A large lepton asymmetry could be generated in the Early Universe by oscillations of active to sterile neutrinos with a small mixing angle sin 2 \theta < 10^-2. The final order of magnitude of the lepton asymmetry \eta is mainly determined…
Light sterile neutrinos mixing with the active ones have been recently proposed to solve different anomalies observed in short-baseline oscillation experiments. These neutrinos can also be produced by oscillations of the active neutrinos in…
We consider active-sterile neutrino oscillations in the early universe in an inhomogeneous isocurvature background. We show that very small initial baryonic seed-inhomogeneities can trigger a growth of very large amplitude spatial…
We have provided a numerical study of the influence of the resonant active-sterile neutrino oscillations between electron and sterile neutrinos, on the primordial production of helium-4. The evolution of the neutrino ensembles was followed…
While the cosmic baryon asymmetry has been measured at high accuracy to be 6.1*10^-10, a corresponding lepton asymmetry could be as large as 10^-2 if it hides in the neutrino sector. It has been known for some time that a large asymmetry…
We review the consequences of neutrino mixing in the early universe. For both active-sterile mixing or mixing between three active neutrinos only, the consequences of oscillations depend crucially upon the size of the universe's lepton…
We consider some consequences of the presence of a cosmological lepton asymmetry in the form of neutrinos. Relic neutrino degeneracy enhances the contribution of massive neutrinos to the present energy density of the Universe, and modifies…
The primordial neutrino asymmetry leaves profound imprints on the evolution history of the universe, which can be constrained by cosmological observations, including Big Bang Nucleosynthesis (BBN), Cosmic Microwave Background (CMB), and…
Effects of neutrino free streaming is evaluated on the primordial spectrum of gravitational radiation taking both neutrino chemical potential and masses into account. The former or the lepton asymmetry induces two competitive effects,…
It has been proposed that an asymmetry in the electron neutrino sector may be generated by resonant active-sterile neutrino transformations during Big Bang Nucleosynthesis (BBN). We calculate the change in the primordial $^4$He yield $Y$…
We calculate Boltzmann neutrino energy transport with self-consistently coupled nuclear reactions through the weak-decoupling-nucleosynthesis epoch in an early universe with significant lepton numbers. We find that the presence of lepton…
We examine the sterile neutrino dark matter production in the primordial plasma with lepton asymmetry unequally distributed over different neutrino flavors. We argue that with the specific flavor fractions, one can mitigate limits from the…
A large neutrino asymmetry is an interesting possibility for cosmology, which can have significant observable consequences for nucleosynthesis and the cosmic microwave background. However, although it is a possibility, there is no obvious…