TY - JOUR
T1 - Search for solar electron anti-neutrinos due to spin-flavor precession in the Sun with Super-Kamiokande-IV
AU - Super-Kamiokande Collaboration
AU - Abe, K.
AU - Bronner, C.
AU - Hayato, Y.
AU - Ikeda, M.
AU - Imaizumi, S.
AU - Ito, H.
AU - Kameda, J.
AU - Kataoka, Y.
AU - Miura, M.
AU - Moriyama, S.
AU - Nagao, Y.
AU - Nakahata, M.
AU - Nakajima, Y.
AU - Nakayama, S.
AU - Okada, T.
AU - Okamoto, K.
AU - Orii, A.
AU - Pronost, G.
AU - Sekiya, H.
AU - Shiozawa, M.
AU - Sonoda, Y.
AU - Suzuki, Y.
AU - Takeda, A.
AU - Takemoto, Y.
AU - Takenaka, A.
AU - Tanaka, H.
AU - Yano, T.
AU - Akutsu, R.
AU - Han, S.
AU - Kajita, T.
AU - Okumura, K.
AU - Tashiro, T.
AU - Wang, R.
AU - Xia, J.
AU - Bravo-Berguño, D.
AU - Labarga, L.
AU - Marti, Ll
AU - Zaldivar, B.
AU - Blaszczyk, F. D.M.
AU - Kearns, E.
AU - Raaf, J. L.
AU - Stone, J. L.
AU - Wan, L.
AU - Wester, T.
AU - Pointon, B. W.
AU - Bian, J.
AU - Griskevich, N. J.
AU - Ishino, H.
AU - Ito, Shintaro
AU - Koshio, Y.
N1 - Funding Information:
We gratefully acknowledge the cooperation of the Kamioka Mining and Smelting Company, Japan . The Super-Kamiokande experiment has been built and operated from funding by the Japanese Ministry of Education, Culture, Sports, Science and Technology , the U.S. Department of Energy , and the U.S. National Science Foundation . Some of us have been supported by funds from the National Research Foundation of Korea NRF-2009-0083526 (KNRC) funded by the Ministry of Science, ICT, and Future Planning, South Korea and the Ministry of Education, Japan 2018R1D1A3B07050696 , 2018R1D1A1B07049158 , the Japan Society for the Promotion of Science , the National Natural Science Foundation of China under Grants No. 11620101004 , the Spanish Ministry of Science, Universities and Innovation (grant PGC2018-099388-B-I00 ), the Natural Sciences and Engineering Research Council (NSERC) of Canada , the Scinet and Westgrid consortia of Compute Canada , the National Science Centre, Poland 2015/18/E/ST2/00758 , the Science and Technology Facilities Council (STFC) and GridPPP, UK , the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie grant agreement no. 754496 , H2020-MSCA-RISE-2018 JENNIFER2 grant agreement no. 822070 , and H2020-MSCA-RISE-2019 SK2HK grant agreement no. 872549 . This analysis was supported also by KAKENHI Grant-in-Aid for Scientific Research (C) No. 20K03998 .
Funding Information:
We gratefully acknowledge the cooperation of the Kamioka Mining and Smelting Company, Japan. The Super-Kamiokande experiment has been built and operated from funding by the Japanese Ministry of Education, Culture, Sports, Science and Technology, the U.S. Department of Energy, and the U.S. National Science Foundation. Some of us have been supported by funds from the National Research Foundation of KoreaNRF-2009-0083526 (KNRC) funded by the Ministry of Science, ICT, and Future Planning, South Korea and the Ministry of Education, Japan2018R1D1A3B07050696, 2018R1D1A1B07049158, the Japan Society for the Promotion of Science, the National Natural Science Foundation of China under Grants No. 11620101004, the Spanish Ministry of Science, Universities and Innovation (grant PGC2018-099388-B-I00), the Natural Sciences and Engineering Research Council (NSERC) of Canada, the Scinet and Westgrid consortia of Compute Canada, the National Science Centre, Poland2015/18/E/ST2/00758, the Science and Technology Facilities Council (STFC) and GridPPP, UK, the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie grant agreement no. 754496, H2020-MSCA-RISE-2018 JENNIFER2 grant agreement no. 822070, and H2020-MSCA-RISE-2019 SK2HK grant agreement no. 872549. This analysis was supported also by KAKENHI Grant-in-Aid for Scientific Research (C) No. 20K03998.
Publisher Copyright:
© 2022 The Authors
PY - 2022/6
Y1 - 2022/6
N2 - Due to a very low production rate of electron anti-neutrinos (ν̄e) via nuclear fusion in the Sun, a flux of solar ν̄e is unexpected. An appearance of ν̄e in solar neutrino flux opens a new window for the new physics beyond the standard model. In particular, a spin-flavor precession process is expected to convert an electron neutrino into an electron anti-neutrino (νe→ν̄e) when neutrino has a finite magnetic moment. In this work, we have searched for solar ν̄e in the Super-Kamiokande experiment, using neutron tagging to identify their inverse beta decay signature. We identified 78 ν̄e candidates for neutrino energies of 9.3 to 17.3 MeV in 2970.1 live days with a fiducial volume of 22.5 kiloton water (183.0 kton⋅year exposure). The energy spectrum has been consistent with background predictions and we thus derived a 90% confidence level upper limit of 4.7×10−4 on the νe→ν̄e conversion probability in the Sun. We used this result to evaluate the sensitivity of future experiments, notably the Super-Kamiokande Gadolinium (SK-Gd) upgrade.
AB - Due to a very low production rate of electron anti-neutrinos (ν̄e) via nuclear fusion in the Sun, a flux of solar ν̄e is unexpected. An appearance of ν̄e in solar neutrino flux opens a new window for the new physics beyond the standard model. In particular, a spin-flavor precession process is expected to convert an electron neutrino into an electron anti-neutrino (νe→ν̄e) when neutrino has a finite magnetic moment. In this work, we have searched for solar ν̄e in the Super-Kamiokande experiment, using neutron tagging to identify their inverse beta decay signature. We identified 78 ν̄e candidates for neutrino energies of 9.3 to 17.3 MeV in 2970.1 live days with a fiducial volume of 22.5 kiloton water (183.0 kton⋅year exposure). The energy spectrum has been consistent with background predictions and we thus derived a 90% confidence level upper limit of 4.7×10−4 on the νe→ν̄e conversion probability in the Sun. We used this result to evaluate the sensitivity of future experiments, notably the Super-Kamiokande Gadolinium (SK-Gd) upgrade.
KW - Electron antineutrinos
KW - Neutrino–antineutrino oscillation
KW - Neutron tagging
KW - Solar neutrino
KW - Water Cherenkov detector
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U2 - 10.1016/j.astropartphys.2022.102702
DO - 10.1016/j.astropartphys.2022.102702
M3 - Article
AN - SCOPUS:85126629624
SN - 0927-6505
VL - 139
JO - Astroparticle Physics
JF - Astroparticle Physics
M1 - 102702
ER -