Model independent information on solar neutrino oscillations

We present the results of a Bayesian analysis of solar neutrino data in terms of ${\nu }_e\to {\nu }_{\mu ,\tau }$ oscillations, independent from the standard solar model predictions for the solar neutrino fluxes. We show that such a model independent analysis allows us to constrain the values of the neutrino mixing parameters in limited regions around the usual regions. Furthermore, there is a strong indication in favor of large neutrino mixing and large values of $\Delta m^2$ (the LMA region). We calculate also the allowed ranges of the neutrino fluxes and we show that they are in good agreement with the standard solar model prediction. In particular, the ratio of the ${}^8\mathrm{B}$ flux with its standard solar model prediction is constrained in the interval $[0.45,1.42]$ with 99.73% probability. Finally, we show that the hypothesis of no neutrino oscillations is strongly disfavored in a model independent way with respect to the hypothesis of neutrino oscillations.