The validity of the nucleon charge exchange model for (${\pi }^{\pm }, \pi N$) reactions is tested by comparing cross sections for (${\pi }^{\pm }, \pi N$) reactions near the $\Delta \mathrm{}\left(1232\right)\mathrm{}$ resonance on the odd-$Z$ nuclei ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$, ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$, ${}_{}{}^{23}{}_{}{}^{}\mathrm{Na}$ ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$, and ${}_{}{}^{31}{}_{}{}^{}\mathrm{P}$ that were measured by observing the $\gamma$ decays of the residual nuclei with cross sections calculated from the model. The model reproduces the general trend of the data, but not the detailed features. Comparison of experimental and calculated cross sections indicates that the reactions are largely quasifree, in agreement with our earlier results for self-conjugate nuclei.

NUCLEAR REACTIONS ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$, ${}_{}{}^{19}{}_{}{}^{}\mathrm{F}$, ${}_{}{}^{23}{}_{}{}^{}\mathrm{Na}$, ${}_{}{}^{27}{}_{}{}^{}\mathrm{Al}$, ${}_{}{}^{31}{}_{}{}^{}\mathrm{P}$, (${\pi }^{\pm }, \pi N$), $E\simeq 200$ MeV; detected $\gamma \text{'}\mathrm{s}$, Ge(Li); measured $90°\sigma$ for residual levels; deduced $\sigma$ ratios, reaction mechanism; compared results with N-CEX model.

• Received 27 May 1982

DOI:https://doi.org/10.1103/PhysRevC.26.2084