A Lithium Experiment as the Stringent Test of the Theory of Stellar Evolution

We show that a lithium experiment has a potential to confirm or reject the value 1.5% of the solar luminosity attributed to a CNO-cycle by the SSM and to prove that the difference between total energy release of the Sun and what is produced in a hydrogen sequence is really produced in CNO cycle. This will be the stringent test of the theory of stellar evolution and the termination of the long-standing goal - the neutrino spectroscopy of the interior of the Sun. At the present time one can see no other way to solve this task, it can be accomplished only with a lithium detector utilizing its high sensitivity to CNO-neutrinos and very high accuracy in the theoretical evaluation of the cross-section of neutrino capture by 7Li. The analyses shows that although a lithium detector is a radiochemical one, principally it is possible to find separately the fluxes of 13N- and 15O-neutrinos.