Giant resonances in the 26Mg(e,e'α0)22Ne reaction

The fivefold differential cross section of the reaction 26Mg(e,e'c) was measured for transferred momenta of 0.35 and 0.54fm-1 and emitted particle angles from -10 degree to 270 degree with respect to the transferred-momentum direction. Angular correlation functions for the emitted α0 were obtained from the data. A model-independent analysis allowed us to obtain the E0, E1, and E2 multipole components of the 26Mg(e,e'α0)22Ne cross section, between 14 and 26 MeV of excitation energy. The E1 component shows a bump around 16.5 MeV, associated with the T< isospin component of the giant dipole resonance. The evaluated strengths associated with the α0 decay channel, presented in percentage of the respective energy-weighted sum rules are 0.45(7)% for E1, 1.4(3)% for E2, and 0.2(1)% for E0. copyright 1997 The American Physical Society