Determination of Solar Neutrino Oscillation Parameters using 1496 Days of Super-Kamiokande-I Data

TL;DR

This paper analyzes 1496 days of Super-Kamiokande-I data to determine solar neutrino oscillation parameters, finding a preferred Large Mixing Angle solution with specific ranges for mass difference and mixing angle.

Contribution

It provides a comprehensive fit to solar neutrino data, narrowing down the allowed oscillation parameter space and confirming the Large Mixing Angle solution.

Findings

Large Mixing Angle solution is favored at 98.9% confidence

Mass square difference $\Delta m^2$ ranges from 3 to 19 x 10^{-5} eV^2

Mixing angle $ heta$ has $ an^2 heta$ between 0.25 and 0.65

Abstract

A number of different fits to solar neutrino mixing and mass square difference were performed using 1496 days of Super-Kamiokande-I's solar neutrino data. These data select two allowed areas at large neutrino mixing when combined with either the solar $^8$B flux prediction of the standard solar model or the SNO interaction rate measurements. A global fit combining SK data with the solar neutrino interaction rates measured by Homestake, SNO, Gallex/GNO and SAGE prefers a single allowed area, the Large Mixing Angle solution, at the 98.9% confidence level. The mass square difference $\Delta m^2$ between the two mass eigenstates ranges from about 3 to $19\times10^{-5}$eV$^2$, while the mixing angle $\theta$ is in the range of $\tan^2\theta\approx$0.25--0.65.