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High-K Isomers in 176W and Mechanisms of K-Violation

B. Crowell·P. Chowdhury·D. J. Blumenthal·S. J. Freeman·C. J. Lister·M. P. Carpenter·R. G. Henry·R. V. F. Janssens·T. L. Khoo·T. Lauritsen·Y. Liang·F. Soramel·I. G. Bearden
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Abstract

An isomer, with t1/2 = 35 +- 10 ns and J, Kpi = 14, 14+, has been observed in the nucleus 176W using the reaction 150Nd(30Si,4n) at a beam energy of 133 MeV. The isomer exhibits an unusual pattern of decay in which the _majority_ of the flux proceeds directly to states with =0, bypassing available levels of intermediate K. This severe breakdown of normal K-selection rules in 176W is compared with recent observations of K-violation in neighboring nuclei, within the framework of proposed theoretical approaches. The available data on these K-violating decays seem to have a consistent explanation in models of K-mixing which include large-amplitude fluctuations of the nuclear shape.

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B. Crowell, P. Chowdhury, D. J. Blumenthal, S. J. Freeman, C. J. Lister, M. P. Carpenter, R. G. Henry, R. V. F. Janssens, T. L. Khoo, T. Lauritsen, Y. Liang, F. Soramel, I. G. Bearden. 1995-02-21. High-K Isomers in 176W and Mechanisms of K-Violation. https://doi.org/10.1103/physrevc.53.1173

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