Anomalous collective modes in atomic nuclei within the proton-neutron interacting boson model

Abstract

Novel collective modes characterized by a $B_{4/2}$ ratio ($\equiv B(E2;4_1^{+}\to 2_1^{+})/B(E2;2_1^{+}\to 0_1^{+})$) less than 1.0 that were observed recently have been identified within the proton-neutron interacting boson model (IBM-2) using the consistent-$Q$ Hamiltonian. These modes are shown to give rise to triaxial spectral features, including significant band mixing. The results provide a compelling explanation for the deeply suppressed $B_{4/2}$ ratio observed in ${}^{166}$W, ${}^{168,170}$Os, and ${}^{172}$Pt, offering new insights into the $B(E2)$ anomaly phenomenon in neutron-deficient nuclei.

9 page, 4 figures

References in corpus (7)

• Quantum phase transitions in the interacting boson model
• Phase structure of the two-fluid proton-neutron system
• Triaxiality in the interacting boson model
• Structure of krypton isotopes within the interacting boson model derived from the Gogny energy density functional
• The emergent dynamical symmetry at the triple point of nuclear deformations
• Triaxial rotor modes in finite-N boson systems
• Quadrupole and octupole states in ${}^{152}$Sm using the proton-neutron interacting boson model

Cited by in corpus (2)

• The IBM Description of the B(E2) Anomaly: Dynamical Triaxiality and Configuration Mixing
• Probing Quadruple Deformation in Transitional Nuclei via Angular Momentum Projection