Impact of non-standard neutrino-electron interactions on Big Bang Nucleosynthesis

Abstract

Neutrino non-standard interactions (NSI) with electrons, predicted in many extended theoretical models of particle physics, are known to alter the picture of neutrino decoupling from the cosmic plasma. We update previous analyses of neutrino decoupling in the presence of NSI with electrons, extending the parameter space in order to provide, for the first time, a full study of their effect on the production of light elements during Big Bang Nucleosynthesis (BBN). We compare the BBN bounds on non-universal and flavour-changing NSI parameters with the constraints from terrestrial experiments. Our results show that the limits from BBN are significantly less stringent than the experimental bounds, but they are complementary and can provide a test of neutrino physics at different temperature scales and epochs.

Comments: 19 pages, 7 figures, 2 tables. Version 2 addresses an inconsistent treatment of the initial baryon-to-photon ratio when varying the NSI parameters, that affected the final deuterium abundance. The main conclusions are unchanged