Yf. Yen et al., PION ELASTIC-SCATTERING FROM POLARIZED C-13 IN THE ENERGY REGION OF THE P-33 RESONANCE, Physical review. C. Nuclear physics, 50(2), 1994, pp. 897-908
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 signific
antly different from zero for pi- scattering. For pi+ at T(pi) = 130 M
eV and for both pi- and pi+ at all other energies, the A(y) are mostly
consistent with zero. Blastic differential cross sections were measur
ed using an unpolarized C-13 target. Both the analyzing-power and cros
s-section data were compared with predictions using a variety of nucle
ar 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 fa
ctor 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.