The neutrino mass hierarchy is one of the neutrino fundamental properties yet to be determined. We introduce a method to determine neutrino mass hierarchy by comparing the events of neutral current (NC) interactions, ν(ν¯)+ p→ν(ν¯)+ p, and inverse beta decays (IBD), ν¯e+ p→n+e+, of supernova neutrinos from accretion and cooling phases in scintillation detectors. Neutrino flavor conversions inside the supernova are sensitive to neutrino mass hierarchy. Due to Mikheyev-Smirnov-Wolfenstein effects, the full swapping of ν¯e flux with the ν¯x (x= µ, τ) one occurs in the inverted hierarchy, while such a swapping does not occur in the normal hierarchy. As a result, the ratio of high energy IBD events to NC events for the inverted hierarchy is higher than the ratio for the normal hierarchy. Since the luminosity of ν¯e is larger than that of νx in accretion phase while the luminosity of ν¯e becomes smaller than that of νx in cooling phase, we calculate this ratio for both accretion and cooling phases. By analyzing the change of this event ratio from accretion phase to cooling phase, one can determine the neutrino mass hierarchy.
|期刊||Proceedings of Science|
|出版狀態||Published - 7月 2017|
|事件||2017 European Physical Society Conference on High Energy Physics, EPS-HEP 2017 - Venice, Italy|
持續時間: 5 7月 2017 → 12 7月 2017