50 MeV pi + and pi - scattering from 12C.

Differential cross sections were measured for 50 MeV {pi}{sup +} and {pi}{sup {minus}} elastic scattering from {sup 12}C and for 50 MeV {pi}{sup +} inelastic scattering to the (4.44 MeV, 2{sup +}), (7.65 MeV, 0{sub 2}{sup +}), (9.64 MeV, 3{sup {minus}}), (12.71 MeV, 1{sup +}), and (15.11 MeV, 1{sup +}) levels in {sup 12}C. Comparisons of the data obtained in this study to data taken previously for these states resolve discrepancies between the earlier data sets. Using a recently discussed procedure, one-step and coupled-channels calculations using a modified MSU potential were performed. The results of both one-step and coupled-channels calculations describe the data for the ground, first, and third excited states, indicative of the collective isoscalar structure of those states. The one-step analysis fails to describe the excitation of the 0{sub 2}{sup +} state. The coupled-channels calculations are more successful in describing those data, indicating that the failure of the one-step calculations may be attributed to coupled-channels effects.