Resonant Production of Sterile Neutrinos in the Early Universe

Author: Gilbert, Lauren Ann

Year: 2016

Degree: Senior thesis (Major)

Advisor: Unknown, Unknown

Committee Member: None, None

Option: Physics

DOI: 10.7907/BKTV-8H10

Abstract

We examine the cosmological impacts of a light resonantly produced sterile neutrino in the early universe. Such a neutrino could be produced through lepton number-driven Mikheyev-Smirnov-Wolfenstein conversion of active neutrinos, resulting in a non-thermal spectrum of both sterile and active neutrinos. If this process occurs during weak decoupling and big bang nucleosynthesis, it would affect the electron neutrino flux and therefore the n/p ratio. This allows us to use observations of primordial helium (Y_p), primordial deuterium (D/H), and N_eff to place limits on this process.