Evidence of Antineutrinos from Distant Reactors Using Pure Water at SNO

Phys Rev Lett. 2023 Mar 3;130(9):091801. doi: 10.1103/PhysRevLett.130.091801.


The SNO+ Collaboration reports the first evidence of reactor antineutrinos in a Cherenkov detector. The nearest nuclear reactors are located 240 km away in Ontario, Canada. This analysis uses events with energies lower than in any previous analysis with a large water Cherenkov detector. Two analytical methods are used to distinguish reactor antineutrinos from background events in 190 days of data and yield consistent evidence for antineutrinos with a combined significance of 3.5σ.