Evidence of Antineutrinos from Distant Reactors using Pure Water at SNO+

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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 3.5$\sigma$.