Large-energy single hits at JUNO from atmospheric neutrinos and dark matter

Large liquid scintillator detectors, such as JUNO, present a new opportunity to study neutral current events from the low-energy end of the atmospheric neutrinos, and possible new physics signals due to light dark matter. We carefully study the possibility of detecting ???large-energy singles??? (LES), i.e., events with visible scintillation energy > 15 MeV, but no other associated tags. For an effective exposure of 20 kton ??? yr and considering only Standard Model physics, we expect the LES sample to contain ???40 events from scattering on free protons and ???108 events from interaction with carbon, from neutral current interactions of atmospheric neutrinos. Backgrounds, largely due to ?? decays of cosmogenic isotopes, are shown to be significant only below 15 MeV visible energy. The LES sample at JUNO can competitively probe a variety of new physics scenarios, such as boosted dark matter and annihilation of galactic dark matter to sterile neutrinos.

Automated summary

Large liquid scintillator detectors, such as JUNO, provide a new opportunity to study low-energy atmospheric neutrinos and possible new physics signals related to light dark matter. In this study, we carefully investigate the possibility of detecting "large-energy singles" (LES) events. The results show that JUNO can competitively probe a variety of new physics scenarios.