Quasiparticle and $\gamma$-band structures in $^{156}$Dy

TL;DR

This paper investigates the excited band structures in $^{156}$Dy using advanced microscopic models, confirming that new observed bands are $b3$-bands based on two-quasineutron configurations, thus providing a detailed theoretical understanding.

Contribution

It applies the microscopic triaxial projected shell model and QRPA to identify the nature of new excited bands in $^{156}$Dy, confirming their $b3$-band structure based on quasineutron configurations.

Findings

New excited bands are $b3$-bands based on two-quasineutron configurations.

The models successfully reproduce the observed band structures.

The results support the conjecture from experimental work.

Abstract

Excited band structures recently observed in $^{156}$Dy are investigated using the microscopic triaxial projected shell model (TPSM) approach and the quasiparticle random phase approximation (QRPA) based on the rotating mean-field. It is demonstrated that new observed excited bands, tracking the ground-state band, are the $\gamma$-bands based on the excited two-quasineutron configurations as conjectured in the experimental work.