Pion elastic scattering from polarized C13 in the energy region of the P33 resonance

Analyzing powers A(y) were measured for pi+ and pi- elastic scattering from polarized C-13 at incident pion energies T(pi) near the P-33 pi-nucleon resonance. At T(pi) = 130 MeV, the values of A(y) are significantly different from zero for pi- scattering. For pi+ at T(pi) = 130 MeV and for both pi- and pi+ at all other energies, the A(y) are mostly consistent with zero. Blastic differential cross sections were measured using an unpolarized C-13 target. Both the analyzing-power and cross-section data were compared with predictions using a variety of nuclear structure and reaction models. The analyzing power was found to be strongly sensitive to the quadrupole spin-flip part of the transition. The data of this work complement measurements of the magnetic form factor by electron scattering. The pion A(y) data are not reproduced by calculations using wave functions that fit the magnetic form factor at low momentum transfers.