Studying the decay data of I-130*

Detection of fission products (FPs) is at the basis of several applications, from reactor science, to non-proliferation and nuclear forensics. In most cases, an accurate quantification of FPs is only possible when the decay data of these isotopes - such as half-life, characteristic gamma-ray energies and intensities - are well known. This is not always the case, and - for many FPs - the current knowledge of decay data comes from measurements that were performed when gamma-ray spectroscopy was in its infancy.

A new campaign to precisely determine gamma-ray intensities of selected FPs is currently underway at Brookhaven National Laboratory. In this work, we present the results for I-130, a so-called “blocked” FP, of particular interest for nuclear forensics. Measuring the amount of I-130 relative to other well-known FPs can, in fact, provide valuable information about the initial fission event that produced it. 

I-130 was produced via the Te-130(p,n) reaction at the BNL Tandem Van de Graaff facility, and assayed at Argonne National Laboratory using the Gammasphere array. The results of precision intensities measurement and a revised decay scheme will be presented.