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arXiv · hep-ph/9305205

The Earth Effect in the MSW Analysis of the Solar Neutrino Experiments

Naoya Hata·Paul Langacker
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Abstract

We consider the Earth effect in the MSW analysis of the Homestake, Kamiokande, GALLEX, and SAGE solar neutrino experiments. Using the time-averaged data and assuming two-flavor oscillations, the large-angle region of the combined fit extends to much smaller angles (to $\sin^22θ\simeq 0.1$) than when the Earth effect is ignored. However, the additional constraint from the Kamiokande II day-night data excludes most of the parameter space sensitive to the Earth effect independent of astrophysical uncertainties, and leaves only a small large-angle region close to maximal mixing at 90\% C.L. The nonadiabatic solution remains unaffected by the Earth effect and is still preferred. Both theoretical and experimental uncertainties are included in the analysis.

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Naoya Hata, Paul Langacker. 1993-05-03. The Earth Effect in the MSW Analysis of the Solar Neutrino Experiments. https://doi.org/10.1103/physrevd.48.2937

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