Theory of Hindered Gamow-Teller Matrix Elements

Abstract

The commutator method which was previously proposed for the purpose of calculating hindered matrix elements is applied to the Gamow.Teller beta matrix elements of heavier nuclei. It is shown that a number of empirical ft-values of the unfavored transitions can be well reproduced in terms of the conventional pairing model without invoking the phenome­ nological effective coupling constant. It is also shown that the !-forbidden transitions can be treated on the same footing as the unfavored ones. In such a treatment tensor forces play an important role. General forms of the effective single-body transition operators are derived on the basis of the commutator method, and qualitative discussions are given.