A Search for Electron Antineutrino Appearance at the $\Delta m^2 \sim$ 1 $\mathrm{eV}^{2}$ Scale

TL;DR

This study searched for electron antineutrino appearance at the  m^2 scale using MiniBooNE data but found results consistent with background, providing no evidence for the hypothesized oscillations.

Contribution

First MiniBooNE search for   antineutrino oscillations at this mass scale with a large data sample, reporting no significant excess.

Findings

Observed events match background predictions within uncertainties.

No significant excess detected at low or high energies.

Results are inconclusive regarding the   oscillation hypothesis.

Abstract

The MiniBooNE Collaboration reports initial results from a search for $\bar{\nu}_{\mu}\to\bar{\nu}_e$ oscillations. A signal-blind analysis was performed using a data sample corresponding to $3.39 \times 10^{20}$ protons on target. The data are consistent with background prediction across the full range of neutrino energy reconstructed assuming quasielastic scattering, $200 < E_{\nu}^{QE} < 3000$ MeV: 144 electron-like events have been observed in this energy range, compared to an expectation of $139.2 \pm 17.6$ events. No significant excess of events has been observed, both at low energy, 200-475 MeV, and at high energy, 475-1250 MeV. The data are inconclusive with respect to antineutrino oscillations suggested by data from the Liquid Scintillator Neutrino Detector at Los Alamos National Laboratory.