K isomers in Cm isotopes via deep-inelastic and transfer reactions

ORAL

Abstract

K isomers in $^{246}$Cm and $^{248}$Cm (Z = 96) were populated via deep-inelastic and transfer reactions using a $^{209}$Bi beam at $\sim $ 15{\%} above the Coulomb barrier, incident on a long-lived $^{248}$Cm target. This reaction mechanism has been employed for the first time in trans-plutonium nuclei to study high-K isomers. The out-of-beam data were collected using Gammasphere in different time regimes ranging from 80 microseconds up to 8 seconds to adjust to different isomer half-lives. The half-life of a known 8$^{-}$ isomeric state in $^{246}$Cm has been measured to be $\sim $ 1 s. A new high-K isomer with K$^{\pi }$ = (8$^{-})$ has also been discovered in $^{248}$Cm. These K$^{\pi }$ = 8$^{-}$ isomers have the same underlying neutron [624]7/2 x [734]9/2 configuration as is observed in the isotones $^{250}$Fm and $^{252}$No. These new data on high-K isomers will add to the limited knowledge of single-particle and pair-gap energies in heavy actinides.

*Supported by USDOE Grants DE-FG02-94ER40848 and W-31-109-ENG-38

Authors

  • U.S. Tandel

  • P. Chowdhury

  • S.K. Tandel

  • A.J. Knox

  • C.M. Wilson

    • University of Massachusetts Lowell
  • I. Ahmad

  • M.P. Carpenter

  • J.P. Greene

  • S. Gros

  • R.V.F. Janssens

  • T.L. Khoo

  • F.G. Kondev

  • T. Lauritsen

  • C.J. Lister

  • D. Peterson

  • A. Robinson

  • D. Seweryniak

  • X. Wang

  • S. Zhu

    • Argonne National Laboratory