A new neutrino source for the study of the solar neutrino physics in the vacuum-matter transition region

Production of a neutrino source through proton induced reaction is studied by using the particle transport code, GEANT4. Unstable isotope such as ${}^{27}$Si can be produced when ${}^{27}$Al target is bombarded by 15 MeV energetic proton beams. Through the beta decay process of the unstable isotope, a new electron-neutrino source in the 1.0 $\sim$ 5.0 MeV energy range is obtained. Proton induced reactions are simulated with JENDL High Energy File 2007 (JENDL/HE-2007) data and other nuclear data. For radioactive decay processes, we use “G4RadioactiveDecay” model based on the Evaluated Nuclear Structure Data File (ENSDF). We suggest target systems required for future’s solar neutrino experiments, in particular, for the vacuum-matter transition region. As for the detection system of the new neutrino source, we evaluate reaction rates for available radiochemical detectors and LENA type scintillator detector. Possibility of detecting sterile neutrinos is also discussed.