Initial measurement of reactor antineutrino oscillation at SNO+

TL;DR

The SNO+ collaboration presents its first spectral analysis of reactor antineutrino oscillations, constraining neutrino mass differences with initial data and aiming for improved precision in future measurements.

Contribution

First spectral analysis of reactor antineutrino oscillations at SNO+ using 114 tonne-years of data, providing initial constraints on neutrino mass-squared difference.

Findings

Best-fit Δm²₁₂ = (8.85^{+1.10}_{-1.33}) × 10^{-5} eV²

Measurement consistent with previous results

Expected to improve precision with more data

Abstract

The SNO+ collaboration reports its first spectral analysis of long-baseline reactor antineutrino oscillation using 114 tonne-years of data. Fitting the neutrino oscillation probability to the observed energy spectrum yields constraints on the neutrino mass-squared difference $\Delta m^2_{21}$. In the ranges allowed by previous measurements, the best-fit $\Delta m^2_{21}$ is (8.85$^{+1.10}_{-1.33}$) $\times$ 10$^{-5}$ eV$^2$. This measurement is continuing in the next phases of SNO+ and is expected to surpass the present global precision on $\Delta m^2_{21}$ with about three years of data.