A Model Independent Approach to Future Solar Neutrino Experiments

We discuss here what model independent information about properties of neutrinos and of the sun can be obtained from future solar neutrino experiments (SNO, Super-Kamiokande). It is shown that in the general case of transitions of solar $\nu_e$'s into $\nu_\mu$ and/or $\nu_\tau$ the initial $^8\mathrm{B}$ neutrino flux can be measured by the observation of NC events. From the CC measurements the $\nu_e$ survival probability can be determined as a function of neutrino energy. The general case of transitions of solar $\nu_e$'s into active as well as sterile neutrinos is considered. A number of relations between measurable quantities the test of which will allow to answer the question whether there are sterile neutrinos in the solar neutrino flux on the earth are derived. Transitions of solar $\nu_e$'s into active and sterile states due to neutrino mixing and Dirac magnetic moments or into active left-handed neutrinos and active right-handed antineutrinos due to neutrino mixing and Majorana transition magnetic moments are also considered. It is shown that future solar neutrino experiments will allow to distinguish between the cases of Dirac and Majorana magnetic moments.