The optical model and distorted-wave analysis of cross-sections for the scattering of the 24-28 MeV alpha particles from 28Si

Abstract

The interaction of alpha particles with nuclei is still not well understood [1, 2]. In particular, difficulties arise in the scattering on A = 4n nuclei [3]. It seems that a simultaneous analysis of the elastic and inelastic processes permits solving some of these problems. Our analysis is based on the experimental data for the elastic and inelastic scattering of alpha particles on 28Si nuclei, obtained with the Cracow U-120 cyclotron. The angular distributions for the elastic [4] and inelastic [5] scattering leading to the first two excited states in 28Si were measured for the alpha bombarding energies of 24, 25, 26, 26.5, 27 and 28 MeV in the angular range from 2 5 ' to 179' (in lab system). The elastic process was described by means of the optical model and the inelastic one by the distorted wave theory. The possibility of resolving some of the optical model ambiguities was studied.