Atomic-Excitation Effects on Nuclear Reactions

Atomic-excitation effects arising from sudden nuclear recoil are shown to be a significant factor in broadening the 14.23-MeV resonance in ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$($p$,$p$)${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ measured with a high—energy-resolution polarized beam. The total width of the resonance is found to be 1010 ±30 eV.