M. Fatyga

Intermediate-mass-fragment production in the reaction of 200 MeV 3He with Ag☆

Abstract Energy spectra of Z = 4–12 fragments emitted in the reactions of 198.6 MeV 3He with natAg were measured over the full angular range. Back-angle data are consistent with evaporation from the compound nucleus; the spectra evolve with Z from maxwellian to gaussian shapes, in agreement with earlier theoretical predictions. A two-component moving source model gives evidence for the existence of a strong non-equilibrium component, with a steep Z−5.3 dependence. The data are compared with the predictions of an accreting source model.

Limitations on linear momentum transfer in 14N induced reactions on 238U at EA=15, 20, 25 and 30MeV☆

Abstract Linear momentum transfer distributions have been dermimined for 14 N induced reactions on 238 U by measuring the folding angle between two coincident fission fragments. The data follow the systematic trends previously established for alpha conjugate projectile nuclei. Over the range of energies investigated, the most probable linear momentum transfer has not reached a limiting value. Extrapolation of the present results indicates that complete fusion should cease to be a relevant reaction mechanism above incident energies of E A =40−45 MeV

Source properties of intermediate mass fragments emitted in the 270 MeV3He + 232Th reaction☆

Abstract Triple coincidences between intermediate mass fragments (IMFs) and angle-correlated fission fragments were measured in the 270 MeV 3 He + 232 Th reaction. These measurements demonstrate that on the average IMF emission occurs prior to fission from a source which carriers 75–80% of the beam momentum. It was deduced that the average number of IMFs per fragmentation event is close to unity. The dependence of the fission probability on the IMF emission angle and atomic number suggests that fragments emitted at forward angles come from more peripheral collisions than those emitted at very backward angles.