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How to measure the spreading width for decay of superdeformed nuclei

D. M. Cardamone·C. A. Stafford·B. R. Barrett
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Abstract

A new expression for the branching ratio for the decay via the E1 process in the normal-deformed band of superdeformed nuclei is given within a simple two-level model. Using this expression, the spreading or tunneling width Gamma^downarrow for superdeformed decay can be expressed entirely in terms of experimentally known quantities. We show how to determine the tunneling matrix element V from the measured value of Gamma^downarrow and a statistical model of the energy levels. The accuracy of the two-level approximation is verified by considering the effects of the other normal-deformed states.

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D. M. Cardamone, C. A. Stafford, B. R. Barrett. 2003-04-04. How to measure the spreading width for decay of superdeformed nuclei. https://doi.org/10.1103/physrevlett.91.102502

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