Decay of Nuclear Giant Resonance States Following Electroexcitation

Nucleon emission following inelastic electron scattering by a nucleus is described as a two-step process, in which a single isolated nuclear level is excited by the incident electron, and then subsequently decays to a state of the daughter nucleus by emitting a proton or neutron. General formulas are derived for the nucleon and electron angular distributions with the help of Racah algebra. Wigner $R$-matrix theory is then used to interpret the angular distributions in the reactions ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}(e,e^{\prime }p){}_{}{}^{11}{}_{}{}^{}\mathrm{B}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}(e,e^{\prime }p){}_{}{}^{15}{}_{}{}^{}\mathrm{N}$ with excitation of the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ giant dipole states, as measured by Dodge and Barber.