Pion Elastic Scattering from Carbon and Oxygen at 30 MeV

Measurements of elastic scattering were made for ${\pi }^{+}$ and ${\pi }^{-}$ beams at 30 MeV on a carbon target and ${\pi }^{+}$ on oxygen at 30 MeV. A magnetic spectrometer utilizing wire spark chambers was used to measure the momenta of the scattered pions over the angular range 40-120 deg. The energy resolution was about 4 Me V full width at half maximum at 30 MeV, which is sufficient to resolve the first excited states of carbon and oxygen. Inelastic scattering from the lower excited states has been estimated. Fits of the Kisslinger optical model to the data have been made.