Neutrino magnetic moments, flavor mixing, and the SuperKamiokande solar data
Abstract
Description
We find that magnetic neutrino-electron scattering is unaffected by oscillations for vacuum mixing of Dirac neutrinos with only diagonal moments and for Majorana neutrinos with two flavors. For MSW mixing, these cases again obtain, though the effective moments can depend on the neutrino energy. Thus, e.g., the magnetic moments measured with $\barν_e$ from a reactor and $ν_e$ from the Sun could be different. With minimal assumptions, we find a new limit on $μ_ν$ using the 825-days SuperKamiokande solar neutrino data: $|μ_ν| \le 1.5\times 10^{-10} μ_B$ at 90% CL, comparable to the existing reactor limit.
4 pages including two inline figures. New version has 825 days SK result, some minor revisions. Accepted for Physical Review Letters
4 pages including two inline figures. New version has 825 days SK result, some minor revisions. Accepted for Physical Review Letters