On a possibility to determine the S factor of the HEP process in experiments with thermal (cold) neutrons

The problem of the magnitude of the S--factor of the hep process $p + {^3\mathrm{He}} \to {^4\mathrm{He}} + e^+ + \nu_e$ is one of the most important unsolved problems in nuclear astrophysics. The magnitude of $S(hep)$ has also an important impact on the interpretation of the Super-Kamiokande solar neutrino results in terms of neutrino oscillations. We point out the possiblity to determine the major hadronic contribution to $S(hep)$ from the measurement of the total cross section of the process $n + {^3\mathrm{H}} \to {^4\mathrm{He}} + e^- + \bar{\nu}_e$ in experiments with high intensity beams of thermal or cold neutrons