A proposal is considered to use a beta-active source with a very high activity (tritium, 10MCi) to reduce the experimental limitation of the neutrino magnetic moment by at least an order of magnitude (to 1–2 Bohr picomagnetons) and to observe coherent neutrino scattering on the He-4 atom (for the first time).
To solve these problems, it is necessary to master the methods for registering energy releases in matter during the interaction between particles in the range of 0.1-10 eV. The main attention is paid to two types of calorimetric detectors with ultralow (15-40 mK) operating temperature − based on superfluid helium-4 (a completely new type of detector) and based on silicon.