Nuclear-charge distribution in fission: Cumulative yields of short-lived krypton and xenon isotopes from thermal-neutron fission of 235U

摘要: Abstract Experiments are described in which use was made of the very large emanating powers barium stearate and uranyl for determination cumulative yields a number krypton xenon isotopes formed thermal-neutron fission 235U. The results, expressed as fraction total chain yield, are: 89Kr, 0·960 ± 0·004, 90Kr, 0·86 0·02; 91Kr, 0·59 0·01; 92Kr, 0·31 139Xe, 0·82 140Xe, 141Xe, 0·21 143Xe, (8·5 0·5) × 10−3; 144Xe, (1·1 0·1) 10−3. These data along with previously reported independent-yield used construction an empirical curve most probable primary charge (ZP) vs. mass number. In regions where shell edges absent is about equidistant complementary numbers from stable (ZA) lines light heavy fragments proposed postulate equal-charge displacement; present ZP makes smooth continuous transition. tends to approach remain close 50-proton edge. It some evidence presented that distribution (for given number) distorted uranium near Z = 50 42 because 50-42 proton split favoured, at least partly expense 51-41 49–53 splits.