6533b7d9fe1ef96bd126c42c
RESEARCH PRODUCT
Unstable massive tau-neutrinos and primordial nucleosynthesis
S. H. HansenAlexander D. DolgovDmitry V. SemikozSergio Pastorsubject
PhysicsNuclear and High Energy PhysicsParticle physicsScalar (mathematics)FOS: Physical sciencesFísicaMassless particleHigh Energy Physics - PhenomenologyMAJORANAHigh Energy Physics - Phenomenology (hep-ph)Big Bang nucleosynthesisKinetic equationsHigh Energy Physics::ExperimentNeutrinodescription
The impact of unstable Majorana tau neutrinos on primordial nucleosynthesis is considered. The mass and lifetime of nu_tau are taken in the intervals 0.1-20 MeV and 0.001-400 sec respectively. The studied decay modes are nu_tau -> nu_mu + phi and nu_tau -> nu_e + phi, where phi is a massless (or light) scalar. Integro-differential kinetic equations are solved numerically without any simplifying assumptions. Our results deviate rather strongly from earlier calculations. Depending on mass, lifetime, and decay channels of the nu_tau, the number of effective neutrino species (found from He4), in addition to the 3 standard ones, varies from -2 to +2.5. The abundances of H2 and Li7 are also calculated.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1998-09-30 | Nuclear Physics B |