EXCITATION AND DECAY OF GIANT-RESONANCES IN THE CA-40(E,E'X) REACTION

The Ca-40(e,e'x) reaction has been investigated for excitation energie s between 8 and 26 MeV and momentum transfers from 0.25 to 0.66 fm-1 a t the continuous-wave electron accelerators MAMI at Mainz and S-DALINA C at Darmstadt. A multipole decomposition of the cross sections reveal s strongly fragmented E2 (plus E0) strength around 14 and 17 MeV in co ntrast to all theoretical predictions. Angular correlations of proton decay are described over the entire energy range by a continuum random -phase-approximation approach. A comparison of the branching ratios to statistical model calculations provides information on the dominant d amping mechanism.