Precise β-Decay Measurements of Long-Lived Fission Products
ORAL
Abstract
Our understanding of the fragment mass distributions following fission impacts many applications, including reactor-neutrino studies, nuclear forensics, and stockpile stewardship science. The γ-ray emissions following the β-decay of fission products provide a reliable signature that is often used to identify relative yields and distributions from fission. However, the uncertainties in the existing nuclear data for γ-ray intensities and β-decay branching ratios for some of the isotopes used in these applications range from 5-30%, which propagates to significant error contributions in fission-chain yield calculations. To address this issue, we have developed an experimental approach to precisely measure γ-ray branching ratios following the decay of long-lived fission products. We have identified 161Tb and 115mCd as two important cases where the data can be significantly improved, and we prepared reactor-irradiated radioactive samples for measurement with our newly established on-site detection system at LLNL. We will present results from recent measurements on these isotopes.
*This work was performed under the auspices of the U.S. Department of Energy by the U.S. Department of Energy National Nuclear Security Administration through the Nuclear Science and Security Consortium under Award Nos. DE- NA0003180 and DE-NA0003996. The project was funded by the U.S. Department of Energy, National Nuclear Security Administration, Office of Defense Nuclear Nonproliferation Research and Development (DNN R&D).This work was also performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. Lawrence Livermore National Security, LLC.
–
Presenters
-
Isabel E Hernandez
- UC Berkeley