@article{77d88ba14dc9449cb8e489942b1929fd,
title = "Search for solar electron anti-neutrinos due to spin-flavor precession in the Sun with Super-Kamiokande-IV",
abstract = "Due to a very low production rate of electron anti-neutrinos ({\=ν}e) via nuclear fusion in the Sun, a flux of solar {\=ν}e is unexpected. An appearance of {\=ν}e 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→{\=ν}e) when neutrino has a finite magnetic moment. In this work, we have searched for solar {\=ν}e in the Super-Kamiokande experiment, using neutron tagging to identify their inverse beta decay signature. We identified 78 {\=ν}e 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→{\=ν}e conversion probability in the Sun. We used this result to evaluate the sensitivity of future experiments, notably the Super-Kamiokande Gadolinium (SK-Gd) upgrade.",
keywords = "Electron antineutrinos, Neutrino–antineutrino oscillation, Neutron tagging, Solar neutrino, Water Cherenkov detector",
author = "{Super-Kamiokande Collaboration} and K. Abe and C. Bronner and Y. Hayato and M. Ikeda and S. Imaizumi and H. Ito and J. Kameda and Y. Kataoka and M. Miura and S. Moriyama and Y. Nagao and M. Nakahata and Y. Nakajima and S. Nakayama and T. Okada and K. Okamoto and A. Orii and G. Pronost and H. Sekiya and M. Shiozawa and Y. Sonoda and Y. Suzuki and A. Takeda and Y. Takemoto and A. Takenaka and H. Tanaka and T. Yano and R. Akutsu and S. Han and T. Kajita and K. Okumura and T. Tashiro and R. Wang and J. Xia and D. Bravo-Bergu{\~n}o and L. Labarga and Ll Marti and B. Zaldivar and Blaszczyk, {F. D.M.} and E. Kearns and Raaf, {J. L.} and Stone, {J. L.} and L. Wan and T. Wester and Pointon, {B. W.} and J. Bian and Griskevich, {N. J.} and Kropp, {W. R.} and S. Locke and M. Ishitsuka",
note = "Publisher Copyright: {\textcopyright} 2022 The Authors",
year = "2022",
month = jun,
doi = "10.1016/j.astropartphys.2022.102702",
language = "English",
volume = "139",
journal = "Astroparticle Physics",
issn = "0927-6505",
publisher = "Elsevier",
}