STP1228: Neutron Dosimetry with the 58Ni(n,p)58Co Reaction at Short-Decay Times

    Griffin, PJ
    Sandia National Laboratories, Nuclear System Research, Albuquerque, NM

    Holm, CV
    Sandia National Laboratories, Nuclear Facilities & Diagnostics, Albuquerque, NM

    Vehar, DW
    Sandia National Laboratories, Nuclear Facilities & Diagnostics, Albuquerque, NM

    Kelly, JJG
    Sandia National Laboratories, Nuclear System Research, Albuquerque, NM

    Pages: 10    Published: Jan 1994


    Abstract

    The 58Ni(n,p)58Co reaction is a very attractive choice for use as a neutron fluence monitor foil in reactor irradiations. The most important drawback to this reaction is the interference from the 9.15-h half-life 58mCo metastable state. A methodology is presented in this paper to allow the 58gCo ground-state activity to be read at short decay times and to be converted into the total 58tCo activity with no significant increase in the measurement uncertainty. This methodology involves modeling the 58mCo/58tCo population ratio. Both theoretical and experimental estimates of the energy dependence of this ratio are presented. A method is presented to accurately measure this ratio. An empirical model of the energy dependence of this ratio is presented to allow simple estimates of the ratio to be made prior to a measurement.

    Keywords:

    neutron, metrology, monitor foil, 58, Ni(n,p), 58, Co, 58m, Co, reactor irradiation, isomer ratio


    Paper ID: STP15110S

    Committee/Subcommittee: E10.08

    DOI: 10.1520/STP15110S


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