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Department of Physics & Astronomy

[ J. Y. Yang and Jonghee Yoo]  Search for Periodic Time Variations of the Solar   8  B    Neutrino Flux between 1996 and 2018 in Super-Kamiokande (published in PRL)

June 17, 2024l Hit 484

We report a search for time variations of the solar 8B neutrino flux using 5804 live days of Super-Kamiokande data collected between May 31, 1996, and May 30, 2018. Super-Kamiokande measured the precise time of each solar neutrino interaction over 22 calendar years to search for solar neutrino flux modulations with unprecedented precision. Periodic modulations are searched for in a dataset comprising five-day interval solar neutrino flux measurements with a maximum likelihood method. We also applied the Lomb-Scargle method to this dataset to compare it with previous reports. The only significant modulation found is due to the elliptic orbit of the Earth around the Sun. The observed modulation is consistent with astronomical data: we measured an eccentricity of (1.53±0.35)%, and a perihelion shift of (−1.5±13.5) days.

 
PRL 132241803 (2024)  https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.132.241803