2022/05/14 by Nicholas D. Heller, G. H. Sargsyan, Heller, Nicholas D. +9
Chemistry · Physics and Astronomy · #Advanced NMR Techniques and Applications #FOS: Physical sciences #Molecular spectroscopy and chirality #Nuclear Theory (nucl-th) #Nuclear physics research studies
paper · pdf · doi:10.48550/arxiv.2205.06943
openalex publication_date 2022/05/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We provide new insights into backbending phenomenon within the symmetry-adapted framework which naturally describes the intrinsic deformation of atomic nuclei. For 20Ne, the canonical example of backbending in light nuclei, the ab initio symmetry-adapted no-core shell model shows that while the energy spectrum replicates the backbending from experimental energies under the rigid rotor assumption, there is no change in the intrinsic deformation or intrinsic spin of the yrast band around the backbend. For the traditional example of 48Cr, computed in the valence shell with empirical interactions, we confirm a high-spin nucleus that is effectively spherical, in agreement with previous models. However, we find that this spherical distribution results, on average, from an almost equal mixing of deformed prolate shapes with deformed oblate and triaxial shapes. Microscopic calculations confirm the importance of spin alignment and configuration mixing, but surprisingly unveil no anomalous increase in moment of inertia. This finding opens the path toward further understanding the rotational behavior and moment of inertia of medium-mass nuclei.