Speaker
Yuuki Nakano
(Kamioka Observatory)
Description
Super-Kamiokande (SK), a 50 kton water Cherenkov detector in Japan, observes $^{8}$B solar neutrinos with neutrino-electron elastic scattering. SK searches for distortions of the solar neutrino energy spectrum caused by the edge of the MSW resonance in the core of the Sun. It also searches for a day/night solar rate asymmetry induced by the matter in the Earth. A combined analysis of the all SK spectral, day/night and absolute rate measurements as well as all solar neutrino and KamLAND data is presented. The installation of new front-end electronics in 2008 marks the beginning of the 4th phase of SK (SK-IV). With the improvement of the water circulation system, calibration methods, reduction cuts, this phase achieved the lowest energy threshold thus far (~3.5 MeV kinetic energy). SK observed solar neutrinos for about 18 years, that is more than 5,000 days. This long operation covers about 1.5 solar activity cycles. An analysis about a possible correlation between solar neutrino flux and 11 year activity cycle will be presented.
Primary author
Yuuki Nakano
(Kamioka Observatory)
