The Energy Dependence of the Proton-Alpha Reaction to Continuum States

The energy dependence of the (p,α) reactions to the continuum states is studied using the Feshbach-Kerman-Koonin multistep theory for the pre-equilibrium reactions assuming the knockout model and using the Hauser-Feshbach theory for the compound nucleus reactions. The energy dependence of the parameter Wo is related to that of the strength of the effective proton-alpha interaction and hence to that of the alpha-particle optical potential. The formalism is extended to include reactions in which the proton is unbound, and this improves the fit to the experimental data.