Collectivity in neutron-rich Cr isotopes

ORAL

Abstract

Collectivity rapidly develops in neutron-rich nuclei near N = 40 with Z $<$ 28 as protons are removed from the f$_{7/2}$ single-particle state. This collectivity has been inferred from large drops in the energy of the first excited 2$^{+}$ state in even-even Cr and Fe isotopes, as well as an increase in B(E2) along the Fe isotopic chain. Shell-model calculations that include the neutron g$_{9/2}$ and d$_{5/2}$ single-particle states indicate that the enhanced collectivity can be attributed to multi-particle neutron excitations across the N=40 gap. In the odd-odd nuclei, coexistence between spherical and deformed states has been proposed in the low-energy level structures of the Co and Mn isotopes. While recent studies of odd-A nuclei in this region have focused on the Co and Fe isotopes, less is known about the odd-A Cr isotopes. The structure of the odd-A Cr nuclei was investigated through the beta decay of neutron-rich V isotopes produced at the NSCL. The low-energy level schemes of the odd-A Cr isotopes will be presented and discussed.

*This work was supported in part by the National Science Foundation, Grant No. PHY-1102511 and the U.S. Department of Energy National Nuclear Security Administration under Award Number DE-NA0000979.

Authors

  • S. Suchyta

    • National Superconducting Cyclotron Laboratory (MSU)
    • NSCL/MSU
  • S. Liddick

    • NSCL/MSU
  • H. Crawford

    • NSCL/MSU
  • G. Grinyer

    • NSCL/MSU
  • N. Larson

    • NSCL/MSU
  • J. Pereira

    • NSCL/MSU
  • C. Prokop

    • NSCL/MSU
  • A. Schneider

    • NSCL/MSU
  • S. Vinnikova

    • NSCL/MSU
  • C. Chiara

    • U. of M./ANL
  • W. Walters

    • U. of M.
  • M. Carpenter

    • ANL
  • G. Gurdal

    • ANL
  • E. McCutchan

    • ANL
  • S. Zhu

    • ANL