Constraints on neutrino-oscillation parameters from the Kamiokande-II solar-neutrino data

Abstract

An analysis of the Mikheyev-Smirnov-Wolfenstein effect using 1040 days of Kamiokande-II data is reported, which provides constraints on neutrino-oscillation parameters. The measured recoil-electron energy spectrum alone leads to the conclusion that the adiabatic region, 7.2\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}4}$${\mathrm{sin}}^{2}$2\ensuremath{\theta}6.3\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}3}$, \ensuremath{\Delta}${\mathit{m}}^{2}$\ensuremath{\sim}1.3\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}4}$ (eV${)}^{2}$, is disfavored at the 90% confidence level.