The elastic scattering of 25MeV α-particles and neutron shell effects in the A = 50 TO A = 93 mass region

Abstract Experimental elastic scattering angular distributions of 25 MeV α-particles scattered from 28 nuclei ranging from 50Cr to 93Nb have been measured and then analysed in terms of a regular optical model with standard Woods-Saxon geometries for both the real and imaginary potentials. The experimental distributions are well fitted over the whole angular range from 5° to 175° c.m. by the predictions, provided that a smaller than normal diffuseness is used for the imaginary potentials. The usual families of potentials with volume integrals differing by approximately 100 MeV · fm3 are found. The family with volume integral ranging from 540 to 420 MeV· fm3 over the nuclei studied has been c…