Measurement of Reactor Antineutrino Oscillations with 1.46 Kilotonne-Years of Data at SNO

The SNO+ Collaboration reports new results on reactor antineutrino oscillations using data acquired from May 2022 through July 2025. The spectral analysis of a flux dominated by nuclear reactors at 240, 340, and 350 km yields the mass-squared difference Δm_{21}^{2}=(7.91_{-0.25}^{+0.22})×10^{-5}  eV^{2}. This result is compatible with and approaches the precision of the only other long-baseline reactor antineutrino measurement, by KamLAND. Combining these measurements, along with those from solar neutrino experiments, the global values of the neutrino mixing parameters become Δm_{21}^{2}=(7.59±0.17)×10^{-5}  eV^{2} and sin^{2}θ_{12}=0.310±0.012. The analysis of geoneutrinos at SNO+ is also improved, with a measured signal of 48_{-12}^{+14} TNU.