(p, d) Reactions induced by a polarized proton beam

Abstract

Differential cross sections and asymmetries (or analysing powers) have been measured for (p,d) reactions on 32–34S, 48Ca, 49Ti, 53Cr, 57Fe, 58–61Ni, 90–91Zr, 92Mo and 118–119Sn nuclei, with a polarized proton beam, at energies around 20 MeV. Experimental evidence is given for the strong j-dependence of the asymmetry, for the various orbital angular momenta transferred l = 1, 2 and 3, and therefore it is shown that asymmetry measurements in (p, d) reactions, such as in (d, p) reactions, provide reliable spin assignments. DWBA predictions with optical-model potentials obtained from analysis of the elastic scattering data in both proton and deuteron channels, give reasonable fits for the measured (p, d) cross sections and asymmetries, except for the light nuclei 32–34S. In case of transitions involving j-mixing, asymmetry measurements are used to determine the contributions of the different j-values.