Energy Distribution of Fission Fragments From U235 and U233

New measurements have been made of the energy distribution of fission fragments. A coincident pulse technique has been used which measures simultaneously the energies of both fragments of a fission pair. Previous work in this field was limited in statistical accuracy owing to low fission rates. With the Chalk River high flux pile and a 30-channel pulse analyzer a rapid accumulation of data is made possible. The improved statistical accuracy has led to new results on the detailed association of fragment pairs and on the energy variation occurring in each fission mode. A careful comparison of U233 and U235 has been made.