Reactions of light nuclei studied deep underground at Gran Sasso, Italy

New and precise astronomical observations call for nuclear data of equal precision for their interpretation. This will permit a better understanding of big-bang nucleosynthesis and of asymptotic giant branch stars.

Based on the recent experimental study of the 3He(alpha,gamma)7Be nuclear reaction directly in the energy range of big-bang nucleosynthesis, a new experiment to study the 2H(alpha,gamma)6Li reaction at big-bang energies is proposed. The new data will allow to test a possible nuclear solution to the big-bang Li-6 posed by new observations of Li-6 in very old stars.

The 14N(p,gamma)15O reaction determines the rate of the CNO cycle. A new study of this reaction is currently underway at the LUNA accelerator deep underground in Gran Sasso, Italy. The new data can be coupled with observations of low-energy solar neutrinos (for example in the Borexino and SNO+ detectors) in order to determine the solar metallicity.

Satellite-based observations of the decay of radioactive Al-26 allow to determine the rate of supernovae in our galaxy, provided the production process is sufficiently well known. The 25Mg(p,gamma)26Al reaction influences Al-26 production; its rate is under experimental study at LUNA.