Elastic scattering of negative pions from ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ and Ca in the 3,3 resonance region

The elastic scattering cross sections for ${\pi }^{-}-{}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ and ${\pi }^{-}-\mathrm{Ca}$ have been measured at pion kinetic energies 160, 170, 220, 230, and 240 MeV for ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, and at 205 and 215 MeV for Ca. The results are analyzed in terms of the Kisslinger and Laplacian optical model potentials and the obtained potential parameters are compared with the impulse approximation result.

NUCLEAR REACTIONS $\mathrm{Ca}(\pi ,\pi )$, $\mathrm{O}(\pi ,\pi )$, $E=160\mathrm{}-240$ MeV; measured $\sigma (E,\theta )$; deduced optical-model parameters. Natural target, resolution 3 MeV; $\theta =15\mathrm{}-70$, $\Delta \theta =2\mathrm{}°$.