The He3(α,γ)Be7 reaction presently represents the largest nuclear uncertainty in the predicted solar neutrino flux and has important implications on the big bang nucleosynthesis, i.e., the production of primordial Li7. We present here the results of an experiment using the recoil separator ERNA (European Recoil separator for Nuclear Astrophysics) to detect directly the Be7 ejectiles. In addition, off-beam activation and coincidence γ-ray measurements were performed at selected energies. At energies above 1 MeV a large discrepancy compared to previous results is observed both in the absolute value and in the energy dependence of the cross section. Based on the available data and models, a robust estimate of the cross section at the astrophysical relevant energies is proposed.
ASJC Scopus subject areas
- Physics and Astronomy(all)