Limiting Cross Sections for Fission Isomers with Nanosecond Lifetimes Produced in Heavy-Ion Reactions

Abstract

Targets of Pr, Ce, Nd, Ir, Au, and Pb have been bombarded with heavy ions in order to produce fission isomers with nanosecond lifetimes. In all cases, limits for detection were set which were much lower than the cross sections previously reported for these systems. It is concluded that fission isomerism was not observed in the previously reported experiments.