Neutron Emission from the Isomeric Beta-decays of Co-70 measured by VANDLE at NSCL

ORAL

Abstract

Co-70 beta-decays to Ni-70 by way of two isomers, a (6-) isomer with a half-life of 112ms, and a lower spin isomer listed as (3+) with a half-life of 470ms. As the Q-value for the decay of Co-70 to Ni-70 is 12.6 MeV, and the neutron separation energy of 70Ni is 7.3 MeV, neutron emission is energetically possible. As the two beta-decays of Co-70 have a different structure, it is not certain how both will emit neutrons. Neutron emission may also compete with gamma emission to below the neutron separation energy in the beta-decay child. This neutron emission probability depends on the structure of the beta-decay child (Ni-70) and the properties of the neutron emission product (Ni-69). An array of 42 120cm VANDLE bars were used with a YAP(Yttrium Aluminum Perovskite) inorganic scintillator implant detector to measure both the implanted nuclei from the NSCL fragmentation of the 82Se primary beam and their subsequent beta-decay. Analysis of the Co-70 decays resulted in two distinctly different neutron energy spectra associated with the different half-lives. These spectra were compared with a recently developed model, which combines shell model and statistical model calculations.

*This research was sponsored in part by the Office of Nuclear Physics, U.S. Department of Energy under Award No. DE-FG02-96ER40983 (UTK) , and by the National Nuclear Security Administration under the Stewardship Science Academic Alliances program through DOE Award No. DE-NA0003899.

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Presenters

  • Kevin Siegl

    • University of Tennessee
    • University of Tennessee, Knoxville

Authors

  • Kevin Siegl

    • University of Tennessee
    • University of Tennessee, Knoxville

  • Andrew M Keeler

    • University of Tennessee

  • Robert Grzywacz

    • University of Tennessee
    • University of Tennessee and Oak Ridge National Lab
    • University of Tennessee, Knoxville

  • Nathan Brewer

    • Oak Ridge Natl. Lab
    • Oak Ridge national laboratory
    • ORNL
    • Oak Ridge National Laboratory

  • Benjamin P Crider

    • Mississippi State Univ
    • Mississippi State University
    • Department of Physics and Astronomy, Mississippi State University

  • Aleksandra Fijalkowska

    • Rutgers University
    • University of Warsaw

  • Matthew Hall

    • Oak Ridge National Lab

  • Joseph H Hamilton

    • Vanderbilt Univ

  • Sean N Liddick

    • National Superconducting Cyclotron Laboratory
    • Michigan State University, NSCL/FRIB
    • NSCL
    • National Superconducting Cyclotron Laboratory; Department of Chemistry, Michigan State University
    • Michigan State University
    • National Superconducting Cyclotron Laboratory; Michigan State University
    • FRIB

  • Miguel Madurga

    • University of Tennessee
    • University of Tennessee, Knoxville

  • Patrick D O'Malley

    • University of Notre Dame

  • Stan V Paulauskas

    • University of Tennessee

  • Thomas T King

    • University of Tennessee
    • Oak Ridge National Laboratory
    • Oak Ridge National Lab

  • Mustafa M Rajabali

    • Tennessee Tech University
    • Tennessee Technological University

  • Steven Z Taylor

    • University of Tennessee

  • Enhong Wang

    • Vanderbilt Univ

  • Christopher J Zachary

    • Vanderbilt Univ