Competition in rotation-alignment between high-j neutrons and protons in transfermium nuclei

TL;DR

This paper investigates the competition between high-j neutrons and protons during rotation-alignment in transfermium nuclei, providing insights into single-particle states in superheavy elements through theoretical modeling and potential experimental verification.

Contribution

It introduces a systematic study of rotation-alignment and band-crossing phenomena in transfermium nuclei using Projected-Shell-Model calculations, highlighting the competition between neutron and proton high-j orbits.

Findings

Neutrons and protons from high-j orbits strongly compete in rotation-alignment.

The study predicts testable effects related to band-crossing phenomena.

Results offer insights into single-particle levels in superheavy nuclei.

Abstract

The study of rotation-alignment of quasiparticles probes sensitively the properties of high-j intruder orbits. The distribution of very high-j orbits, which are consequences of the fundamental spin-orbit interaction, links with the important question of single-particle levels in superheavy nuclei. With the deformed single-particle states generated by the standard Nilsson potential, we perform Projected-Shell-Model calculations for transfermium nuclei where detailed spectroscopy experiment is currently possible. Specifically, we study the systematical behavior of rotation-alignment and associated band-crossing phenomenon in Cf, Fm, and No isotopes. Neutrons and protons from the high-j orbits are found to compete strongly in rotation-alignment, which gives rise to testable effects. Observation of these effects will provide direct information on the single-particle states in the heaviest nuclear mass region.