Study of refractive structure in the inelastic [formula omitted] scattering at the incident energies of 250 to 1120 MeV

Abstract

The data of inelastic O 16 + O 16 scattering to the lowest 2 + and 3 − excited states of O 16 have been measured at E lab = 250 , 350 , 480 , 704 and 1120 MeV and analyzed consistently in the distorted wave Born approximation (DWBA), using the semi-microscopic optical potentials and inelastic form factors given by the folding model, to reveal possible refractive structure of the nuclear rainbow that was identified earlier in the elastic O 16 + O 16 scattering channel at the same energies. Given the known transition strengths of the 2 1 + and 3 1 − states of O 16 well determined from the ( e , e ′ ) data, the DWBA description of the inelastic data over the whole angular range was possible only if the absorption in the exit channels is significantly increased (especially, for the O 16 + O 2 + ∗ 16 exit channel). Although the refractive pattern of the inelastic O 16 + O 16 scattering was found to be less pronounced compared to that observed in the elastic scattering channel, a clear remnant of the main rainbow maximum could still be seen in the inelastic cross section at E lab = 350 – 704 MeV .