Stabilization of Nuclear Isovector Valence-Shell Excitations

Journal Article · Fri Mar 31 04:00:00 EST 2006 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.96.122501· OSTI ID:20777116

Rainovski, G ^[1]; Pietralla, N ^[1]; Ahn, T ^[1]; Lister, C J; Janssens, R V.F.; Carpenter, M P; Zhu, S ^[2]; Barton, III, C J ^[3]

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1. Department of Physics and Astronomy, SUNY at Stony Brook, Stony Brook, New York 11794-3800 (United States)
2. Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States)
3. Department of Physics, University of York, Heslington, York Y01 5DD (United Kingdom)

Excited states in {sup 138}Ce have been studied via the {sup 12}C({sup 138}Ce,{sup 138}Ce*) Coulomb excitation reaction at 480 MeV. Relative cross sections have been determined from the {gamma}-ray yields observed with Gammasphere. The E2 and M1 strength distributions between the lowest six 2{sup +} states up to 2.7 MeV enables us to identify the 2{sub 4}{sup +} state in {sup 138}Ce as the dominant fragment of the one-phonon 2{sub 1,ms}{sup +} mixed-symmetry state. Mixing between this level and a nearby isoscalar state is observed and is more than 4 times larger than in the neighboring isotone {sup 136}Ba. This is direct evidence that the stability of mixed-symmetry states strongly depends on the underlying subshell structure.

• OSTI ID: 20777116
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 12 Vol. 96; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BARIUM 136
CARBON 12 TARGET
CERIUM 138
COULOMB EXCITATION
CROSS SECTIONS
EXCITED STATES
GAMMA RADIATION
ISOVECTORS
MEV RANGE 100-1000
PHONONS
STABILITY
STABILIZATION
SYMMETRY
VALENCE