The \(\alpha \)-nucleus potential: towards a solution of a long-standing problem

This study presents an overview over \(\alpha \)-nucleus potentials which are the essential ingredient for the calculation of cross sections and astrophysical reaction rates for \(\alpha \)-induced reactions on intermediate mass and heavy nuclei within the statistical model. Recent experimental data for Mo + \(\alpha \) have been chosen as an example to illustrate the properties of several widely used \(\alpha \)-nucleus potentials. The delicate role of the imaginary part of the potential at large radii is discussed which is the origin of the widely discrepant predictions of the different potentials at low energies far below the Coulomb barrier. The Atomki-V2 potential circumvents the complications with the imaginary part and provides very good predictions for the recent Mo + \(\alpha \) data and also for most other recent reactions and is thus an excellent basis for the calculation of reaction rates. But further improvements are possible, and some ideas in this direction are given in the discussion.