B(E2) anomaly and triaxial deformation within a two-fluid SU(3) symmetry

Abstract

The correlation between $B(E2)$ structure and triaxial deformation has been investigated within the framework of the proton-neutron boson model. The analysis reveals that the distinctive feature, characterized by $B(E2;4_1^{+}\to 2_1^{+})/B(E2;2_1^{+}\to 0_1^{+})<1.0$ along with $E(4_1^{+})/E(2_1^{+})>2.0$, can emerge from the triaxial SU(3) symmetry inherent in two-fluid boson systems, attributed to band-mixing effects. This suggests a symmetry-based understanding of the anomalous $E2$ transitions observed in experiments.

Comments: 6 pages, 3 figures