High-K four-quasiparticle states in {sup 138}Gd

Journal Article · Tue Mar 15 04:00:00 EDT 2011 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.83.034311· OSTI ID:21499480

Procter, M G; Cullen, D M; Lumley, N M; Mason, P J. R. ^[1]; Scholey, C; Greenlees, P T; Hirvonen, J; Jakobsson, U; Jones, P; Julin, R; Juutinen, S; Ketelhut, S; Leino, M; Nieminen, P; Nyman, M; Peura, P; Rahkila, P; Ruotsalainen, P; Saren, J; Sorri, J ^[2]

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1. Schuster Laboratory, University of Manchester, Manchester M13 9PL (United Kingdom)
2. Department of Physics, University of Jyvaeskylae, FIN-40014 Jyvaeskylae (Finland)

States above the known K{sup {pi}}=8{sup -} 6 {mu}s isomer in {sup 138}Gd have been populated with the {sup 106}Cd({sup 36}Ar,2p2n) reaction at a beam energy of 180 MeV at the University of Jyvaeskylae, Finland. The recoil-isomer tagging technique was utilized to correlate delayed {gamma}-ray decays, detected in the GREAT focal plane spectrometer, with prompt decays measured in the JUROGAM II spectrometer at the target position. The lifetime of the K{sup {pi}}=8{sup -} isomeric state has been remeasured as 6.2(2) {mu}s. Two high-lying strongly coupled bands have been established with K{sup {pi}}{>=}12{sup -}. Potential-energy surface calculations, in conjunction with g factor measurements, reveal that they are built upon four-quasiparticle structures comprising two-quasineutron plus two-quasiproton configurations. The short half-life or lack of hindrance for the decays from these four-quasiparticle band-head states is reasoned to be a consequence of increased triaxial deformation and mixing due to the high density of states relative to the lower two-quasiparticle 6-{mu}s isomeric state.

• OSTI ID: 21499480
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 3 Vol. 83; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ARGON 36 REACTIONS
CADMIUM 106 TARGET
DECAY
DEFORMATION
DIMENSIONLESS NUMBERS
ELECTROMAGNETIC RADIATION
EMISSION
ENERGY RANGE
EVEN-EVEN NUCLEI
GADOLINIUM 138
GADOLINIUM ISOTOPES
GAMMA RADIATION
HALF-LIFE
HEAVY ION REACTIONS
INTERMEDIATE MASS NUCLEI
IONIZING RADIATIONS
ISOMERS
ISOTOPES
LANDE FACTOR
LIFETIME
MEASURING INSTRUMENTS
MEV RANGE
MEV RANGE 100-1000
MIXING
NEUTRON EMISSION
NUCLEAR DECAY
NUCLEAR DEFORMATION
NUCLEAR REACTIONS
NUCLEI
PROTON-EMISSION DECAY
RADIATIONS
RARE EARTH NUCLEI
RECOILS
SPECTROMETERS
SURFACES
TARGETS