Development of 59Ni/58Ni measurements at CAMS
Corinne Dorais1, Scott Tumey1, Alan Hidy1
1LLNL, Livermore, United States
Nickel-59 is a long-lived radioisotope (t1/2=76,000a) with applications in nuclear security, dosimetry, and cosmochemistry. However, the measurement of 59Ni via AMS is made difficult by the presence of isobaric 59Co. Cobalt and Ni share very similar chemical behavior and are therefore difficult to fully separate using traditional sample purification chemistry. Furthermore, Co can be found in many components of the AMS ion source, target holders, and sample packing materials, in which Co cannot be removed via chemistry. Recent work at the Center for Accelerator Mass Spectrometry (CAMS) at Lawrence Livermore National Laboratory (USA) has focused on developing a method of measuring 59Ni/58Ni on our 10MV FN tandem accelerator. In order to minimize the Co background, new ion source components have been made from materials low in Co. Additionally, a variety of materials have been investigated for target holders and sample packing. Results of these modifications will be presented along with measurement setup, charge state selection, and measurement challenges.
This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. We thank the U.S. Department of Energy’s National Nuclear Security Administration, Office of Defense Nuclear Nonproliferation Research and Development, for financial support.
Corinne is a postdoc at Lawrence Livermore National Laboratory’s Center for Accelerator Mass Spectrometry (CAMS), where her research focuses on AMS method development for nuclear forensics applications. Prior to joining CAMS, Corinne worked as a graduate fellow within the United States National Nuclear Security Administration. She obtained her PhD from the University of Notre Dame (USA) in 2019.