Neutron-pair exchange and alpha exchange between two identical colliding cores, ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ in the first case and ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ in the second case, are correctly described by a generalized Frahn and Venter parametrization of the elastic scattering phase shift. Possibility of a Josephson effect is discussed.

NUCLEAR REACTIONS Elastic scattering ${}_{}{}^{34}{}_{}{}^{}\mathrm{S}$(${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$,${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$) and ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$(${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$,${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$); $E_{{}_{}{}^{32}{}_{}{}^{}\mathrm{S}}=77-97\mathrm{}$ MeV; ${\theta }_{\mathrm{cm}}=30\mathrm{}°-150\mathrm{}°$, $\Delta \theta =1\mathrm{}°$; generalized phase shift analysis: particle exchange between identical cores.

• Received 8 November 1982

DOI:https://doi.org/10.1103/PhysRevC.27.2408