Dispersion relations for (n,n), (n,p), and (n,α) reactions on 39K and 40Ca

Cross sections and differential cross sections of K-39(n,alpha)Cl-36 at En=4.5, 5.5, and 6.5 MeV, and that of Ca-40(n,alpha)Ar-37 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 K-39(n,n), (n,p), and (n,alpha) reactions is determined, and subsequently used in the dispersive optical model (DOM) calculations for Ca-40(n,n), (n,p), and (n,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.