Rick D'Alarcao

Harvesting new isomers in neutron-rich hafnium nuclei

P. Chowdhury”, I. Shestakova”, R. D’Alarcaoa, C.J. Pearsonb, Z. Podolyakb, P.M. Walkerb, C. Wheldonb, D.M. Cullenc, I. Ahmadd, M.P. Carpenterd, R.V.F. Janssensd, T.L. Khood, F.G. Kondevd, C.J. Listerd, D. Seweryniakd and I. Wiedenhoeverd aDepartment of Physics, University of Massachusetts, Lowell, MA 01854, USA bDepartment of Physics, University of Surrey, Guildford GU2 5XH, UK ‘Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE, UK dArgonne Na tl ‘o nal Laboratory, Argonne, IL 60439, USA New multi-quasiparticle K-isomers have been investigated in neutron-rich hafnium nu- clei via inelastic and transfer reactions with a pulsed 238U beam on a lsoHf target. The emphasis of this presentation is on the specific techniques of isolating and characteriz- ing isomers with 2~s half-lives and low cross-sections in the transfer channels using the Gammasphere array. 1. THE PHYSICS Quantum numbers associated with special symmetries of the nuclear wave-function in- vite investigation regarding their limits of validity. One that has received considerable attention now for a number of years is K, the

K-isomers in Hf nuclei at and beyond the neutron-rich edge of β-stability

New high-K isomers are populated in {sup 180,181,182}Hf nuclei via inelastic excitation and transfer reactions, using pulsed {sup 238}U beams on Hf targets. The new data explore K-hindrances for different multipolarities and the role of residual spin-spin interactions for multi-quasiparticle (qp) configurations at the neutron-rich edge of the {beta}-stability line. The mapping of 4-qp K-isomers in the A {approx} 180 region is extended into neutron-rich territory.