Excitation function of the 15. 11 MeV (1/sup +/,T = 1) state in /sup 12/C from (. pi. ,. pi. '. gamma. ) angular correlations

The excitation function of the 15.11 MeV (1/sup +/,T = 1) state in /sup 12/C has been measured by using the (..pi..,..pi..'..gamma..) angular correlation technique. By this method, the background can be suppressed substantially. The relative cross section ratio of the 15.11 MeV (1/sup +/,T = 1) and the 12.71 MeV (1/sup +/,T = 0) state as a function of the pion incident energy is found to show a resonancelike behavior in the region of the ..delta.. resonance, in agreement with previous measurements of Morris et al.