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arXiv · hep-ex/0310064

The Solar Neutrino Day/Night Effect in Super-Kamiokande

Michael Burghard Smy
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Abstract

The time variation of the elastic scattering rate of solar neutrinos with electrons in Super-Kamiokande-I was fit to the day/night variations expected from active two-neutrino oscillations in the Large Mixing Angle region. Combining Super-Kamiokande measurements with other solar and reactor neutrino data, the mixing angle is determined as sin^2theta=0.276+0.033-0.026 and the mass squared difference between the two neutrino mass eigenstates as Delta m^2=7.1+0.6-0.5x10^-5eV^2. For the best fit parameters, a day/night asymmetry of -1.7+-1.6(stat)+1.3-1.2(syst)% was determined from the Super-Kamiokande data, which has improved statistical precision over previous measurements and is in excellent agreement with the expected value of -1.6%.

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Michael Burghard Smy. 2003-10-31. The Solar Neutrino Day/Night Effect in Super-Kamiokande. https://doi.org/10.1016/j.nuclphysbps.2004.11.022

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