Measurement of Short-Lived Fission Product Yields for $^{237}$Np via $\gamma$-ray Spectroscopy

ORAL

Abstract

Accurate fission product yields (FPYs) for neutron-induced fission of $^{237}$Np are important for applied nuclear science. The yields of short-lived fission products $(t_{1/2}$ $\lesssim$ hours$)$ are of particular interest, and are experimentally challenging to measure. High-resolution $\gamma$-ray spectroscopy can be used to determine the amount of various fission fragments produced by the unique $\gamma$-ray signatures of their decay, and does not require time-consuming chemical separation processes. Samples of $^{237}$Np have been irradiated in the Godiva-IV critical assembly, and then measured in a $\gamma$-ray counting setup for approximately 7 days. Hundreds of unique $\gamma$-rays were observed, allowing for the measurement of FPYs for many short-lived isotopes.

*This work was funded by the Office of Defense Nuclear Nonproliferation Research and Development within the U.S. DOE - NNSA. This work was performed under the auspices of the U.S. DOE by LLNL under Contract DE-AC52-07NA27344. The National Criticality Experiments Research Center (NCERC), utilized in this work, is supported by the U.S. DOE Nuclear Criticality Safety Program, funded and managed by the NNSA for the DOE.

–

Authors

  • Sean Burcher

    • Lawrence Livermore Natl Lab
    • University of Tennessee
  • J.T. Harke

    • Lawrence Livermore Natl Lab
  • S.W. Padgett

    • Lawrence Livermore Natl Lab
  • N. Gharibyan

    • Lawrence Livermore Natl Lab
  • N. Howard

    • Lawrence Livermore Natl Lab
  • K. Roberts

    • Lawrence Livermore Natl Lab
  • G. Slavik

    • Lawrence Livermore Natl Lab
  • P. Zhao

    • Lawrence Livermore Natl Lab
  • A.S. Tamashiro

    • Oregon State University
  • B.D. Pierson

    • Pacific Northwest Natl Lab
  • L. Greenwood

    • Pacific Northwest Natl Lab
  • J. Goda

    • Los Alamos Natl Lab
  • D. Hayes

    • Los Alamos Natl Lab
  • J. Hutchinson

    • Los Alamos Natl Lab
  • J. Walker

    • Los Alamos Natl Lab