Further explorations of the ɑ-particle optical model potential at low energies for the mass range A ≈ 45-209.

The recent high-precision measurements of ɑ-particle-induced-reaction data below the Coulomb barrier (B) make possible the understanding of limits and possible improvement of a previous optical model potential (OMP) for ɑ particles on nuclei within the mass number range 45 ≤ A ≤ 209 [M. Avrigeanu et al., Phys. Rev. C 82, 014606 (2010)]. An updated version of this potential is given in the present work concerning mainly an increased surface imaginary-potential depth well below B for A > 130. Moreover, underestimation of reaction cross sections for well-deformed nuclei is removed by using ~ 7% larger radius for the surface imaginary part of this spherical OMP. Improved input parameters based on recent independent data, particularly ɣ-ray strength functions, but no empirical rescaling factor of the ɣ and/or neutron widths have been involved within statistical model calculation of the corresponding (ɑ,x) reaction cross sections. [ABSTRACT FROM AUTHOR]