Alpha-cluster knockout in the O-16(e,e 'alpha)C-12 reaction

摘要

The knockout of a-clusters induced by electrons has been used to study four-nucleon correlations in O-16. For the transition to the ground state of C-12 the (e, e ' alpha) cross section has been measured for three values of the momentum transfer and four values of the missing momentum. The momentum-transfer dependence gives evidence for a quasi-elastic alpha -knockout mechanism. The shape of the measured missing-momentum distribution is reasonably well described by shell-model and cluster-model calculations, but the theoretical curves overshoot the data by a factor three to four. (C) 2001 Elsevier Science B.V. All rights reserved. [References: 40]