We present an evidence of isospin effects in nuclear fission by comparing thefission widths for reactions involving different isospin states of the samecompound nucleus (CN). Yadrovsky suggested this possibility in 1975. Yadrovskyobtained the fission widths for two reaction data sets, namely$^{206}$Pb($\alpha$,f) and $^{209}$Bi(p,f), both leading to same CN, andconcluded that "a nucleus remembers the isospin value of the nuclear statesleading to fission". We obtain the fission decay widths for both the $T_0+1/2$and $T_0-1/2$ states of CN by using two appropriate reaction data sets. We thencompare the fission widths for the two isospin states of CN. More specifically,we have chosen the combination of $^{206}$Pb($\alpha$,f) and $^{209}$Bi(p,f)same as presented in Yadrovsky's paper and $^{235}$U(d,f) and $^{236}$U(p,f)reaction data sets in this study. A significant difference between the ratiosof fission decay widths to total decay widths for different isospin valuessuggests that isospin plays an important role in fission.
展开▼
