Understanding the Effect of Chiral NN Parametrization on Nuclear Shapes From an Ab Initio Perspective

TL;DR

This paper investigates how different chiral NN interaction parametrizations influence nuclear shapes and collectivity in low-lying states of 6Li and 12C using an ab initio symmetry-adapted no-core shell model, revealing limited effects in ground states but significant sensitivity in excited states.

Contribution

First analysis of the impact of chiral NN interaction parametrization on nuclear shape coexistence and collectivity in ab initio calculations of 6Li and 12C.

Findings

Interaction parametrization has limited effect on ground states.

Excited 2+ state of 12C shows significant shape sensitivity.

Emergence of shape coexistence in 12C excited states.

Abstract

The ab initio symmetry-adapted no-core shell model naturally describes nuclear deformation and collectivity, and is therefore well-suited to studying the dynamics and coexistence of shapes in atomic nuclei. For the first time, we analyze how these features in low-lying states of 6Li and 12C are impacted by the underlying realistic nucleon-nucleon interaction. We find that the interaction parametrization has a notable but limited effect on collective shapes in the lowest 6Li and 12C states, while collective structures in the excited 2+ state of 12C are significantly more sensitive to the interaction parameters and exhibits emergent shape coexistence.