Electroexcitation of the nuclear continuum

The power of coincidence electron scattering to probe the nuclear response functions in the continuum region is demonstrated by the example of the /sup 28/Si(e,e'c) reaction in which the charged particle decay products c = p,α are measured in coincidence with the electron which has caused the inelastic excitation. A model-independent analysis of the /sup 28/Si(e,e'c) coincidence data, taken at three momentum transfers, yields E1 and E2/E0 form factors and the respective strength distributions in the giant resonance region of /sup 28/Si (E/sub X/ = 14--22 MeV). The analysis of the (e,e'α0) angular correlation functions separates E0, E1 and E2 excitations. Evidence for the presence of large isovector E2/E0 contributions and sizeable E0 excitations is presented