First - Forbidden Beta Decay near A = 40
نویسنده
چکیده
Shell model calculations in the full sdpf model space are carried out for the known and possible lirst-forbidden beta decays for 34 < A i 44. The main purpose is to study the strong quenching of the unique (dJ = 2) decays, which results from the repulsive nature of the T= 1 particle-hole interaction, and the strong meson-exchange enhancement of the AJ = 0 decays. Procedures for calculating the relevant matrix elements and combining them to form the decay rate are described in detail. Various approximations designed to display more clearly the dependence of the rates on the contributing matrix elements are presented and the associated errors assessed. The results are compared to experiment and conclusions are drawn regarding our present understanding of first-forbidden beta decays. Q 1988 Academic Press, Inc.
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