Isomeric cross sections of fast-neutron induced reactions on ${}^{197}$Au

Recent accurate data obtained for the isomeric cross section of the ${}^{197}$Au$(n,2n)$ reaction provide a valuable opportunity to consider the question of the effective moment of inertia of the nucleus within a local consistent model analysis of all available reaction data for the ${}^{197}$Au target nucleus. Thus, a definite proof of a moment of inertia equal to that of the rigid–body has been obtained for ${}^{196}$Au nucleus while an inference of the half rigid–body value is suggested for the ${}^{194}$Ir nucleus. The usefulness of further measurements at incident energies up to $\ge$40 MeV has also been proved.