Narrow Results

The ultimate goal of nuclear astrophysics, the union of nuclear physics and astronomy, is to provide a comprehensive picture of the nuclear reactions which power the stars and, in doing so, synthesize the chemical elements. Deep underground in the Gran Sasso Laboratory the key reactions of the proton–proton chain and of the carbon–nitrogen–oxygen cycle have been studied down to the energies of astrophysical interest. The main results obtained in the past 20 years are reviewed and their influence on our understanding of the properties of the neutrino, the Sun, and the Universe itself is discussed. Finally, future developments of underground nuclear astrophysics beyond the study of hydrogen burning are outlined.