Optical model analysis of 3He elastic scattering from s-d shell nuclei at 25 MeV
Abstract
Angular distributions of elastically scattered 3He particles from 16O, 18O, 19F, 23Na, 24Mg, 25Mg, 26Mg,27Al,28Si,29Si, 30Si, 31P, 35Cl, 37Cl, 39K and 40Ca nuclei were measured at 25 MeV bombarding energy. The absolute differential cross-section data were analysed in the framework of the standard optical model with either a volume or a surface imaginary part. Three families of parameters were considered. For all these families, the real potential volume integral jr per interacting nucleon pair decreases as the mass number A increases. The family withjr = 380 MeV · fm3 for 40Ca and jr = 590 MeV · fm3 for 16O has been identified with the unique family obtained at higher energies, and is therefore considered as the “physical” family. The matter and charge radii deduced from the analysis are presented. The charge radii are compared with the ones obtained from muonic X-ray transitions and electron scattering measurements.
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