Solar neutrino results from Super-Kamiokande

The results of the third phase of the Super-Kamiokande (SK-III) solar neutrino measurement are presented and combined with the first (SK-I) and the second (SK-II) phase results. In SK-III, due to a water purification system upgrade and water flow tuning in the SK tank, the background level was lowered. Furthermore, with improved detector calibrations, a full detector simulation, and new analysis methods, the systematic uncertainty on the total neutrino flux is estimated to be 2.1%, which is about two thirds of the systematic uncertainty during SK-I. The observed B-8 solar flux in the 5.0 to 20 MeV total electron energy region is 2.32 +/- 0.04 (stat.) +/- 0.05 (sys.) x 10(6) cm(-2)sec(-1), in agreement with previous measurements. By adding SK-III data to SK-I and SK-II, it was found that the energy spectrum and the time variation of solar neutrinos obtained from our measurements favor only the large mixing angle solution (LMA) by constraining the 8B and hep neutrino flux to SNO NC flux and SSM prediction respectively. The oscillation analysis results are also combined with the results of other solar neutrino experiments. The best-fit oscillation parameters are obtained to be sin(2)theta(12) = 0.30(-0.01)(+0.02) (tan(2) theta(12) = 0.42(-0.02)(+0.04) and Delta m(21)(2) = 6.2(-1.9)(+1.1) x 10(-5)eV(2). Combined with KamLAND results, the best-fit oscillation parameters are found to be sin(2) theta(12) = 0.31 +/- 0.01(tan(2) theta(12) = 0.44 +/- 0.03) and Delta m(21)(2) = 7.6 +/- 0.2 x10(-5)eV(2). The B-8 neutrino flux obtained from global solar neutrino experiments is 5.3 +/- 0.2(stat.+sys.)x10(6)cm(-2)s(-1), while the B-8 flux becomes 5.1 +/- 0.1(stat.+sys.)x 10(6)cm(-2)s(-1) by adding KamLAND result. In a three-flavor analysis combining all solar neutrino experiments, the upper limit of sin(2) theta(13) is 0.060 at 95% C.L.. After combination with KamLAND results, the upper limit of sin(2) theta(13) is found to be 0.059 at 95% C.L..