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Violation of the Equivalence Principle in the light of the SNO and SK solar neutrino results

Amitava Raychaudhuri·Arunansu Sil
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Abstract

The SNO result on charged current deuteron disintegration, the SuperKamiokande 1258-day data on electron scattering, and other solar neutrino results are used to revisit the model of neutrino oscillations driven by a violation of the equivalence principle. We use a chisq minimization technique to examine oscillation between the nu(e) and another active neutrino, both massless, and find that within the Standard Solar Model the fit to the SNO and SuperKamiokande spectra are moderately good while a very good fit is obtained when the absolute normalizations of the 8B and hep neutrino fluxes are allowed to vary. The best fit prefers large, but not maximal, mixing, essentially no hep neutrinos, and a 40% reduction in the 8B neutrino flux. The fit to the total rates from the different experiments is not encouraging but when the rates and spectra are considerd together the situation is much improved. We remark on the expectations of the VEP model for the neutral current measurements at SNO.

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Amitava Raychaudhuri, Arunansu Sil. 2001-07-03. Violation of the Equivalence Principle in the light of the SNO and SK solar neutrino results. https://doi.org/10.1103/physrevd.65.073035

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