Cluster-model interpretation of the 6Li(e, e'p) reaction

A microscopic cluster model is used to interpret the proton spectral function obtained in recent 6Li(e, e'p)5He experiments in the quasielastic region. The 6Li g.s. is represented by a pair of spherically distortable α and deuteron clusters, while the residual five-nucleon system, '5He', is described as a continuum of α+n and t+d clusterizations with the cluster distortions in the main component of each partial wave taken into account. The comparison with experiment is made through an unfactorized distorted-wave impulse approximation. It was found that the cluster distortions only moderately influence the 5He-p energy and momentum structure of 6Li, but the proper treatment of the continuum is indispensable even for the reproduction of energy-integrated quantities. Considering that no parameter is fitted to the (e, e'p) data, the agreement with experiment is satisfactory. Appreciable discrepancy has only been found in the energy continuum above the ground-state resonance of 5He. An improvement here seems to require a component in the 6Li wave function of summed nucleon spin zero and summed orbital momentum unity, which can be generated most naturally as a type of 5He+p structure. (orig.)