A Search for Proton Decay into e+π° Irvine-Michigan-Brookhaven Collaboration
Observations were made 1570 mwe underground with an 8000 metric ton water Cherenkov detector. During a live-time of 80 days no events consistent with the decay p → e+π° were found in a fiducial mass of 3300 metric tons. We conclude that the limit on the lifetime for bound plus free protons divided by the e+π° branching ratio is τ/B > 1.9 × 1031 yr. (90% confidence). Observed cosmic ray muons and neutrinos are compatible with expectations.
KeywordsProton Decay Atmospheric Neutrino Free Proton Cherenkov Light Track Direction
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References and Footnotes
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