Towards a Model Independent Treatment of Future Solar Neutrino Data

Possibilities of a model independent treatment of the data from future real-time solar neutrino experiments (SNO, Super-Kamiokande and others) are discussed. It is shown that in the general case of transitions of the initial solar $\nu_e$'s into $\nu_\mu$ and/or $\nu_\tau$ the total flux of initial $^8\mathrm{B}$ neutrinos and the $\nu_e$ survival probability can be determined directly from the experimental data. Relations between observable quantities are derived, which, if confronted with the experimental data, would allow to reveal the presence of sterile neutrinos in the solar neutrino flux on the earth. Neutrino transitions due to spin and resonant spin-flavour precession in the magnetic field of the sun are shortly discussed.