Spin effects inπ-nucleus scattering in the region of theΔ(3,3) resonance

We present the first measurements of spin effects in ${\pi }^{+}$ elastic and inelastic scattering from complex nuclei, ${}_{}{}^{15}{}_{}{}^{}$N→${\left(\right(1/2\mathrm{}}^{\mathrm{-}}$) and ${}_{}{}^6{}_{}{}^{}$Li→${(1\mathrm{}}^{+}$). For the case of ${}_{}{}^{15}{}_{}{}^{}$N→, the analyzing power $A_y$ was measured at $T_{\pi }$=164 MeV between 60° and 100°. Although large values of $A_y$ are predicted by theory, the data are consistent with zero. For the case of ${}_{}{}^6{}_{}{}^{}$Li→, the analyzing power ${\mathrm{iT}}_{11}$ was measured at $T_{\pi }$=134 and 164 MeV, between 50° and 110°. Large values of ${\mathrm{iT}}_{11}$ were found at some angles, but the measured angular distributions differ considerably from theoretical predictions.