We examine the dependence of the ${}_{}{}^6{}_{}{}^{}\mathrm{Li}(\gamma , {\pi }^{+}){}_{}{}^6{}_{}{}^{}\mathrm{He}$ cross section on the pion optical potential and on the nuclear size parameters within the context of the distorted-wave impulse approximation. Other factors affecting the cross section are also considered and it is shown that the theoretical prediction remains about 60% higher than the observed cross section. Comparison to radiative pion capture in ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$ is made.

• Received 15 August 1974

DOI:https://doi.org/10.1103/PhysRevLett.33.1316