The case of solar neutrinos

During a thermonuclear reaction taking place inside the Sun, 1.8x1038 neutrinos are formed in one second in the so-called proton-proton chain. The reaction only proceeds in the central region of the Sun while most solar plasma serves as a cover protecting the solar thermonuclear reactor from cooling. This thermostatic property of the thermonuclear reaction is the reason why the solar luminous intensity (solar constant K approximately equal to 1.4 kW.m-2) has not almost changed during ages. Neutrinos only slightly interact with other particles and through neutrino capture direct data could thus be obtained on the thermonuclear reaction process. The results of the experiment by R. Davis with capturing neutrinos by means of the 37Cl nuclide showed a value three times lower than theoretical presumptions. Some possible explanations are given of the disagreement and new experiments are suggested with capturing solar neutrinos using 7Li or 71Ga. (B.S.)