Solar neutrino experiments are highly sensitive to sources of conversions in the neutrino flux. In this work, we adapt these searches to nonminimal sterile neutrino models recently proposed to explain the LSND, MiniBooNE, and reactor anomalies. The production of such sterile neutrinos in the Sun, followed by the decay chain with a new scalar , results in upper limits for the neutrino mixing at the per-mille level. We conclude that a simultaneous explanation of all anomalies is in tension with KamLAND, Super-Kamiokande, and Borexino constraints on the flux of solar antineutrinos. We then present other minimal models that violate parity or lepton number, and discuss the applicability of our constraints in each case. Future improvements can be expected from existing Borexino data, as well as from future searches at Super-Kamiokande with added gadolinium.
Bibliographical noteFunding Information:
The authors would like to thank Linyan Wan and Sandra Zavatarelli for correspondence on the SK-IV and Borexino experimental capabilities. We also thank Ivan Esteban and Joachim Kopp for discussions. M. P. is supported in part by the U.S. Department of Energy (Grant No. desc0011842). This research was supported in part by the Perimeter Institute for Theoretical Physics. Research at the Perimeter Institute is supported by the government of Canada through the Department of Innovation, Science, and Economic Development and by the province of Ontario through the Ministry of Research, Innovation, and Science.
U.S. Department of Energy Perimeter Institute for Theoretical Physics Department of Innovation, Science, and Economic Development Government of Canada Province of Ontario Ontario Ministry of Research, Innovation and Science
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