Signatures of the efficiency of solar nuclear reactions in the neutrino experiments

In the framework of the neutrino oscillation scenario, we discuss the influence of the uncertainty on the efficiency of the neutrino emitting reactions ${}^1\mathrm{H}{(p,e}^{+}{\nu }_e{)}^2\mathrm{H}$ and ${}^7\mathrm{Be}(\mathrm{p},\gamma {)}^8\mathrm{B}$ for the neutrino oscillation parameters. We consider solar models with zero-energy astrophysical S factors $S_{11}$ and $S_{17}$ varied within nuclear physics uncertainties, and we test them by means of helioseismic data. We then analyze the neutrino mixing parameters and recoil electron spectra for the presently operating neutrino experiments and predict the results which can be obtained from the recoil electron spectra in Sudbury Neutrino Observatory and Borexino experiments. We suggest that it should be possible to determine tight bounds to $S_{17}$ from the results of the future neutrino experiment, in the case of matter-enhanced oscillations of active neutrinos.