Emergent Soft Monopole Modes in Weakly-Bound Deformed Nuclei

TL;DR

This paper introduces an advanced computational approach to study soft monopole excitations in weakly-bound, deformed nuclei, revealing enhanced collective modes due to weak-binding effects.

Contribution

The implementation of the finite amplitude method for QRPA in deformed coordinate spaces enables detailed analysis of collective excitations in weakly-bound nuclei.

Findings

Enhanced soft monopole strengths observed in Magnesium isotopes.

Weak-binding effects lead to increased collectivity in monopole modes.

The method effectively probes continuum states in deformed nuclei.

Abstract

Based on the Hartree-Fock-Bogoliubov solutions in large deformed coordinate spaces, the finite amplitude method for quasiparticle random phase approximation (FAM-QRPA) has been implemented, providing a suitable approach to probe collective excitations of weakly-bound nuclei embedded in the continuum. The monopole excitation modes in Magnesium isotopes up to the neutron drip line have been studied with the FAM-QRPA framework on both the coordinate-space and harmonic oscillator basis methods. Enhanced soft monopole strengths and collectivity as a result of weak-binding effects have been unambiguously demonstrated.