ANALYSIS OF alpha-208Pb ELASTIC SCATTERING IN A WIDE ENERGY RANGE BY THE S-MATRIX MODEL dagger

The paper analyzes the elastic scattering of alpha-particles on heavy 208Pb nuclei at energies 26-175 MeV/nucleon using the original six-parameter S -matrix model, taking into account the strong absorption and pronounced effects of refraction of scattered waves. By fitting experimental data from the literature, measured in a wide range of energies: 104, 139, 166, 172, 240, 288, 340, 386, 480, and 699 MeV, the diffraction and refractive patterns of scattering have been investigated. The behavior of the found parameters of the model, as well as of the total reaction cross-section, the angles of crossover of the near and far components of the scattering amplitude (Fraunhofer intersection), and the angles of the nuclear rainbow have been studied and a comparison with the differential cross sections calculated according to the optical model is presented.