Projected shell model description for nuclear isomers

TL;DR

This paper introduces an extension of the Projected Shell Model to describe nuclear isomers, including K-isomers and shape isomers, highlighting the importance of K-mixing and potential need for triaxiality.

Contribution

The paper develops a PSM-based method for nuclear isomers, incorporating K-mixing and proposing a scheme for shape isomer configuration mixing.

Findings

K-mixing is effectively implemented for K-isomers.

Triaxiality may be necessary for accurate K-violation description.

A scheme for mixing configurations of different shapes is outlined.

Abstract

Nuclear isomer is a current research focus. To describe isomers, we present a method based on the Projected Shell Model. Two kinds of isomers, K-isomers and shape isomers, are discussed. For the K-isomer treatment, K-mixing is properly implemented in the model. It is found however that in order to describe the strong K-violation more efficiently, it may be necessary to further introduce triaxiality into the shell model basis. To treat shape isomers, a scheme is outlined which allows mixing those configurations belonging to different shapes.