Coherent active-sterile neutrino flavor transformation in the early universe.
We solve the problem of coherent Mikheyev-Smirnov-Wolfenstein resonant active-to-sterile neutrino flavor conversion driven by an initial lepton number in the early Universe. We find incomplete destruction of the lepton number in this process and a sterile neutrino energy distribution with a distinctive cusp and high energy tail. These features imply alteration of the nonzero lepton number primordial nucleosynthesis paradigm when there exist sterile neutrinos with rest masses m(s) approximately 1 eV. This could result in better light element probes of (constraints on) these particles.
Kishimoto
Chad T
CT
Department of Physics, University of California-San Diego, La Jolla, California 92093-0319, USA. ckishimo@ucsd.edu
Fuller
George M
GM
Smith
Christel J
CJ