Dispersion relations for(n,n),(n,p),and(n,α)reactions on39Kand40Ca

Abstract

Cross sections and differential cross sections of ${}^{39}\mathrm{K}(n,\ensuremath{\alpha}{)}^{36}\mathrm{Cl}$ at $En=4.5,$ 5.5, and 6.5 MeV, and that of ${}^{40}\mathrm{Ca}(n,\ensuremath{\alpha}{)}^{37}\mathrm{Ar}$ at $En=5$ and 6 MeV were measured. These data and other available experimental data were used in optical model calculations which contain a dispersion relation term. One set of parameters for dispersive optical potentials of ${}^{39}\mathrm{K}(n,n),$ $(n,p),$ and $(n,\ensuremath{\alpha})$ reactions is determined, and subsequently used in the dispersive optical model (DOM) calculations for ${}^{40}\mathrm{Ca}(n,n),$ $(n,p),$ and $(n,\ensuremath{\alpha})$ reactions. A good description of the experimental data with DOM is achieved, and the results are compared with that of the spherical optical model.