Enhanced α-particle optical potential at low energies, for the mass range A∼45-209

An updated optical potential is thus provided for α-particles on nuclei within the mass number range 45≤A≤209, below the Coulomb barrier (B), on the basis of recent high-precision measurements of α-particle induced reaction data below B that made possible the understanding of actual limits and possible improvement of the α-particle optical-model potentials. The main revision concerns actually only the surface imaginary potential depth at the lowest α-particle energies well below B, and in fact only for the mass range above A∼130. A further regional point is the underestimation of reaction cross sections for the rare-earth nuclei by using the spherical optical potential unless a 7% larger value of the surface imaginary potential radius is taken into account. Involvement of this potential for further description of both the scattering and α-particles induced reactions is moreover discussed in the present work, of equal interest for nuclear astrophysics and nuclear technology for fusion devices.