MEASUREMENT OF FRAGMENT MASS-ENERGY CORRELATIONS FOR CM-248(S,F) - FAR-OUT ASYMMETRIC FISSION AND COLD FRAGMENTATIONS

A back-to-back ionisation chamber has been used to measure the fission fragment mass-kinetic-energy correlations for Cm-248(s, f). In all ab out 12 x 10(6) fission events were collected. The different distributi ons in the high-yield region are consistent with the existent data. As predicted by the theory of fission channels, the existence of far-out asymmetric fission has been confirmed, but its amplitude is much smal ler than that for Cf-252(s, f) indicating that the barrier of the chan nel corresponding to this channel should be lower for Cf-252(s, f) tha n for Cm-248(s, f). Furthermore, the (E(K)>(M(H)) and sigma(EK)(M(H)) distributions show correlated fluctuations in the far-out asymmetric r egion suggesting the existence of at least two scission configurations with different deformations for the same fragmentation. In the cold-f ission region, the deformed neutron N congruent-to 88 shell dominates the yield.