Inelastic Pion Double Charge Exchange onO16at 240 MeV

The deep-inelastic double-charge-exchange reaction ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}({\pi }^{+}, {\pi }^{-})$ has been measured at 50°, 85°, and 130° with 240-MeV incident pions. The doubly differential cross section is peaked at low outgoing pion energies, as is expected from a double-scattering process, and is nearly isotropic. The integrated cross section is 5.8±0.9 mb. The shape of the differential cross section suggests that the low-energy tail in ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}({\pi }^{+}, {\pi }^{+\prime })$ scattering at the same energy also arises from double scattering.