A model independent analysis of solar neutrino data

Abstract

The results of a solar model independent analysis of the existing solar neutrino data under the assumption of MSW transitions in matter or vacuum oscillations (in the cases of $\nu_{e}$--$\nu_{\mu}(\nu_{\tau})$ and $\nu_{e}$--$\nu_{\mathrm{S}}$ mixing) are presented. The analysis was done in two cases. In the first case no assumptions on the value of the total fluxes of neutrinos from all reactions has been made. In the second case some boundaries for the values of the neutrino fluxes, that take into account the predictions of different standard solar models, are imposed. It is shown that rather large regions of the parameters $ \Delta m^2 $ and $ \sin^2 2\theta $ are excluded by the existing data. It is also shown that the astrophysical solution of the solar neutrino problem can be excluded only in the case in which limitations on the values of the solar neutrino fluxes are imposed.