1997/12/31 by A. D. Dolgov, A.D. Dolgova, Steen H. Hansen +3
Physics and Astronomy · #Neutrino Physics Research #Quantum chaos and dynamical systems #Scientific Research and Discoveries #hep-ph
paper · pdf · doi:10.1016/s0550-3213(98)00307-1
published as Nucl.Phys. B524 (1998) 621-638 · 30 pages, 9 figures, 2 tables, revised figures, minor changes
openalex publication_date 1998/08/01 · arxiv created 1999/02/28 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The influence of a massive Majorana tau-neutrino on primordial nucleosynthesis is rigorously calculated. The system of three integro-differential kinetic equations is solved numerically for the tau-neutrino mass in the interval from 0 to 20 MeV. It is found that the usual assumption of kinetic equilibrium is strongly violated and non-equilibrium corrections considerably amplify the effect. Even a very weak restriction from nucleosynthesis, allowing for one extra massless neutrino species, permits to conclude that mντ< 1 MeV. For a stricter bound, e.g. for dN < 0.3, the limit is mντ< 0.35 MeV.