On the number of neutrons emitted by U236 in the symmetric fission region

INDEPENDENT YIELDS OF 124Sb AND 126sb IN THERMAL NEUTRON INDUCED FISSION AND THEIR IMPLICATION ON THE EMPIRICAL Zp FUNCTION

“…just in the region where proton shell effects are discussed. I t should, however, be pointed out that the original Milton-Fraser curve was interpolated in this region, but that recent measurements by Apalin et al (38) have proved this proper and heavily supports the curve as drawn in Fig. 4 Fig.…”

“…Therefore the dip in the kinetic energy distribution near synlnletric fission should not be explained by a 50 proton shell effect, but should be sought in the large amount of energy going into excitation energy in near symmetric fission fragments, resulting in the emission of a large number of neutrons from these fragments as also observed by Apalin et al (38). This explanation was also given as an alternative by Milton and Fraser (9); however, while this paper was being written (1964), they chose the latter alternative and abandoned the 50 proton shell effect (39).…”

Average Number of Prompt Neutrons fromU235Fission Induced by Neutrons from Thermal to 8 MeV

“…The kinetic energy was found to decrease sharply by approximately 40 MeV as symmetry was approached. Measurements of the neutron emission as a function of mass ratio by Apalin et al 38 have now shown conclusively that this decrease in fragment kinetic energy is matched by an increased neutron yield. Making allowance for the experimental dispersion in fragment mass, Apalin estimated that 6 neutrons are emitted in symmetric fission of U 235 .…”