Line-spectroscopic approach to study of solar neutrinos by cryogenic bolometry of charged and neutral current reactions on 7Li

The astrophysics and the particle physics of solar neutrinos can be tested independently by two line signals induced by neutral (NC) and charged current (CC) neutrino reactions on 7Li, in a high-resolution, bolometric, 4-ton LiF detector. The NC γ-ray line signal measures the flux of neutrinos of all flavors with Eν>0.478 MeV, setting a firm empirical basis for the model-dependent links of the solar reaction chains. The CC signal from the model-independent ''pep'' neutrino line is a ''yes/no'' signal for flavor conservation. The shape of the CC $(---pep$)--- line is a direct thermometric probe of the solar core