The first excited 0{sup +} state in {sup 152}Sm
- WNSL, Yale University, New Haven, Connecticut 06520 (United States)
- Institut fuer Kernphysik der Universitaet zu Koeln (Germany)
- Brookhaven National Laboratory, Upton, New York 11973 (United States)
- Clark University, Worcester, Massachusetts 01610 (United States)
- Institute of Atomic Physics, Bucharest-Magurele (Romania)
The properties of K=0{sup +} excitations in deformed and transitional nuclei have recently been of intense interest. We present results of a study of the deexcitations of the lowest excited 0{sup +} state in {sup 152}Sm from the {epsilon}-decay of {sup 152}Eu, yielding one of the few precisely known values of the branching ratio R{sub 0g}{sup {gamma}}=B(E2;2{sub {gamma}}{sup +}{r_arrow}0{sub 2}{sup +})/B(E2;2{sub {gamma}}{sup +}{r_arrow}0{sub 1}{sup +}) =0.048(4), which is extraordinarily small. From T{sub 1/2}(2{sub {gamma}}{sup +}) we also obtain B(E2;2{sub {gamma}}{sup +}{r_arrow}0{sub 2}{sup +})=0.17 W.u. Values of R{sub 0g}{sup {gamma}} calculated in the interacting boson model (IBA) go to zero extremely rapidly, changing by orders of magnitude for a narrow range of parameter values. {sup 152}Sm is a rare case of a transitional nucleus that lands almost at the minimum. {sup 152}Sm and {sup 154}Gd are the only nuclei from 90{le}N{le}114 where the B(E2) values for all four transitions 2{sub {gamma}}{sup +}{r_arrow}0{sub 2}{sup +}, 2{sub {gamma}}{sup +}{r_arrow}0{sub 1}{sup +}, 0{sub 2}{sup +}{r_arrow}2{sub 1}{sup +}, and 2{sub 1}{sup +}{r_arrow}0{sub 1}{sup +} are now known. In {sup 152}Sm these B(E2) values span three orders of magnitude, from 144 to 0.17 W.u. and are reproduced to within a factor of 2{endash}3 by the IBA. The rather strong B(E2;0{sub 2}{sup +}{r_arrow}2{sub 1}{sup +}) value of 33 W.u. suggest that the 0{sub 2}{sup +} level is an example of a good low energy {beta}-vibration. {copyright} {ital 1998} {ital The American Physical Society}
- OSTI ID:
- 599168
- Journal Information:
- Physical Review, C, Journal Name: Physical Review, C Journal Issue: 4 Vol. 57; ISSN PRVCAN; ISSN 0556-2813
- Country of Publication:
- United States
- Language:
- English
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