An energy-dependent analysis of elastic scattering of ${\pi }^{+}$ from ${}^{12}\mathrm{C},$ ${}^{16}\mathrm{O},$ and ${}^{40}\mathrm{Ca}$ is made based on differential cross sections and (in one case) reaction cross sections. A nonlocal optical model is used to provide the energy variation between data sets. Structure is found in the $s$- and $p$-wave phase shifts.

• Received 3 February 1998

DOI:https://doi.org/10.1103/PhysRevC.58.314