Inclusive Pion Scattering in the (3,3) Resonance Region

Energy spectra from ${\pi }^{+}$ inelastic scattering on ${}_{}{}^4{}_{}{}^{}\mathrm{He}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$, and ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ have been measured at $T_{\pi }=100, 160, \mathrm{and} 220$ MeV. These spectra have prominent features which are qualitatively consistent with quasifree scattering from nucleons. For ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ at low energies, true absorption becomes the dominant fraction of the reaction cross section, and inelastic scattering is strongly inhibited. This is in marked contrast to the behavior of the partial reaction cross sections for the other nuclei.