The independent fission yields in thermal neutron induced fission of 235U have been measured to be (9.5 ± 1.4)•10−6% and (1.04 ± 0.17)•10−3% for 124gSb and 126gSb, respectively. The total independent yields for all isomers of these nuclides are estimated to be (1.2 ± 0.2)•10−5% for 124Sb and (3.7 ± 0.6)•10−3% for 126Sb using a Huizenga–Vandenbosch approach for estimating population of isomeric states.These data do not seem to support a 50 proton shell effect on the Zp function, using the "unique" charge distribution curve of Wahl. A revised Wahl plot based on recent information on neutron emission from individual fission fragments is given and discussed in view of shell effects in fission. It is shown that the effect of the Zp function of the 50 proton shell is very small.
Proton Shell Evolution below
Sn132
: First Measurement of Low-Lying
β
-Emitting Isomers in
Ag123,125
