Identification of isomeric states in the N=73 neutron-deficient nuclei 132Pr and 130La
Taylor, M. J., Alharshan, G. A., Cullen, D., Procter, M. G., Lumley, N. M., Grahn, T., . . . Bai, Z. J. (2012). Identification of isomeric states in the N=73 neutron-deficient nuclei 132Pr and 130La. Physical Review C, 86 (4), 044310. doi:10.1103/PhysRevC.86.044310
Published in
Physical Review CAuthors
Xu, F.R. |
Date
2012Discipline
FysiikkaCopyright
© 2012 American Physical Society. Published in this repository with the kind permission of the publisher.
Decays from isomeric states in the neutron-deficient N = 73 nuclei 132Pr and 130La have been observed for the
first time. Half-lives of 486(70) ns and 2.46(4) μs were measured for two isomeric states in 132Pr. The decay from
the 486 ns (8−) isomer has been interpreted as a hindered E1 transition from the bandhead state of the excited
πh11/2 ⊗ νg7/2 configuration. The decay from the 2.5 μs (8+) isomer is consistent with the Weisskopf estimate
for a low-energy E2 transition. An analogous 0.74(3) μs decay from an (8+) isomer in the neighboring isotone 130La has also been observed which similarly can be explained if the transition has E2 character. The Weisskopf
interpretation for the isomer hindrance is strengthened by the lack of evidence for shape or K isomerism due to
the γ -soft shapes predicted by configuration-constrained potential-energy-surface calculations.