Two-dimensional collective Hamiltonian for chiral and wobbling modes II: Electromagnetic transitions

TL;DR

This paper develops a collective Hamiltonian framework to accurately calculate electromagnetic transitions in chiral and wobbling nuclear modes, improving agreement with particle rotor model results by including quantum fluctuations.

Contribution

It introduces a two-dimensional collective Hamiltonian approach that surpasses mean field approximations for describing electromagnetic transitions in triaxial nuclei.

Findings

Better agreement with particle rotor model for electromagnetic transitions.

Quantum fluctuations improve the accuracy of collective Hamiltonian predictions.

Comparison shows the method's effectiveness over tilted axis cranking approach.

Abstract

The intraband electromagnetic transitions in the framework of collective Hamiltonian for chiral and wobbling modes are calculated. By going beyond the mean field approximation on the orientations of rotational axis, the collective Hamiltonian provides the descriptions on both yrast band and collective excitation bands. For a system with one $h_{11/2}$ proton particle and one $h_{11/2}$ neutron hole coupled to a triaxial rotor ($\gamma=-30^\circ$), the intraband electromagnetic transitions given by the one-dimensional and two-dimensional collective Hamiltonian are compared to the results by the tilted axis cranking approach and particle rotor model. Compared with the tilted axis cranking approach, the electromagnetic transitions given by the collective Hamiltonian have a better agreement with those by the particle rotor model, due to the consideration of the quantum fluctuations.