1996/08/12 by D. P. Kirilova, Daniela Kirilova, M. V. Chizhov · 5 citations
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Dark Matter and Cosmic Phenomena #Neutrino Physics Research #hep-ph
paper · pdf · doi:10.1016/s0370-2693(96)01626-7
published as Phys.Lett. B393 (1997) 375-382 · LaTeX, 7 pages, 6 Postscript figures, figures are included in the revised text (epsf.sty)
arxiv created 1996/08/12 · openalex publication_date 1997/02/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We studied nonequilibrium oscillations between left-handed electron neutrinos and nonthermalized sterile neutrinos in medium for resonant and nonresonant cases. The exact kinetic equations for neutrinos, written in terms of neutrino density matrix in \it momentum space were analyzed. The evolution of neutrino density matrix was numerically calculated. This allowed to study precisely the evolution of the neutrino number densities, energy spectrum distortion and the asymmetry between neutrinos and antineutrinos for each momentum mode. The influence of nonequilibrium oscillations on the primordial production of He-4 was calculated. Cosmological constraints on the oscillation parameters were obtained.