Study of nuclear reactions related to astrophysics

Nuclear reactions involved in the CNO cycle during star evolution become competitive when carbon concentration and the star's temperature are sufficiently high. High-energy g-rays (>4MeV) are emitted because those nuclear reactions are mainly exo-energetic. Those reactions are produced between particles contained in the gas and thermally excited, which correspond to energies lower than 200 keV. Reaction rates and therefore cross sections of these reactions are very important to determine the evolution of the star. Unfortunately, a lack of data exists in the literature concerning the cross sections.
Both accelerators situated at LARN (150 kV SAMES implanter and ALTAÏS Tandetron of 2MV) could help us to determine these cross sections. For example, the cross section of the capture reaction ¹⁴N(p,g)¹⁵O could be measured for energies in the range 20 to 150 keV with the implanter, while the cross section of the reverse ¹H(¹⁴N,g)¹⁵O reaction could be measured at higher energies (between 300 and 4000 keV) using our new Tandetron accelerator.
A better comprehension of the energy creation in the stars will be possible and new star models will be made. This kind of research shows the interactivity between Astrophysicists and Nuclear Physicists.