New parameters for scattering of 18.6 MeV polarized protons
1968; Elsevier BV; Volume: 108; Issue: 3 Linguagem: Inglês
10.1016/0375-9474(68)90326-6
ISSN1873-1554
AutoresP. Kossanyi-Demay, R. de Swiniarski,
Tópico(s)Scientific Research and Discoveries
ResumoOptical-model and coupled-channel calculations are presented for the scattering of 18.6 MeV polarized protons from medium-weight nuclei using parameters which are consistent with the analysis of higher-energy data. Reasonable elastic fits and improved inelastic fits are obtained by reducing the radius of the central real potential with respect to the radius of the imaginary potential which is increased from the previous Perey value. The diffuseness of the real potential is larger than has previously been inferred, while the diffuseness of the imaginary potential is unchanged. The elastic and inelastic data are analysed using a derivative spin-orbit form factor instead of the Thomas form factor usually used to describe the spin-orbit coupling. The fits obtained are in very good agreement with those found by using the usual 1r dependence. The symmetry term or (N−Z)A dependence of the potential is derived either for the central real potential or for the imaginary potential and appears to give satisfactory agreement with other recent optical-model analyses, if the 54Fe data are not taken into account. It is shown that the symmetry terms corresponding to Vs and WD do not depend on the geometrical parameters used for the analysis.
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