Speaker
Description
Reactor neutrino oscillation experiments observe two anomalies in anti-neutrino energy spectra: a total deficit of events, and an event excess in the 5-7 MeV range compared to theory. A total deficit in anti-neutrino flux may support a non-SM sterile neutrino, but both discrepancies may result from inadequate understanding of the reactor fuel cycle. In the 5-7 MeV range first-forbidden $0^-\rightarrow 0^+$ decays account for 30% of the total anti-neutrino ($\bar{\nu}_e$) flux, with $^{92}Rb$ ground-state to ground-state branch (GSB) alone accounting for 30-50% of $0^-\rightarrow 0^+$ $\bar{\nu}_e$ flux. Model predictions will be improved by measuring the $\bar{\nu}_e$ energy spectra from $^{92}Rb$ decay, and measuring the strong GSB ratio with projected 2% accuracy and independent systematics to traditional total absorption spectrometers. Using the TRINAT neutral atom trap, and measured momenta of beta and recoiling $^{92}Sr$ daughter, kinematic reconstruction of $\bar{\nu}_e$ energy spectra, decay Q-value, GSB ratio, and beta-neutrino angular correlation coefficient $a_{\beta\nu}$ are examined experimentally.
