Study of Giant Resonances of ^9Be with the (e, e'n) Reaction(I. Nuclear Physics)

The (e, e' n) cross sections have been measured in the giant resonance region at three momentum transfers. The E1 cross section shows a shallow minimum at 22 MeV. It is believed that the reaction mechanism is different from each other in the both sides of the minimum. The angular distribution of emitted neutrons and the momentum-transfer dependence of the cross section suggest that the E2 component is distributed over a wide energy region. About 40% of branching-ratio is observed to leave the residual ^8Be nucleus at levels of 16.6 and 16.9 MeV.