Novel structure for magnetic rotation bands in 60Ni

TL;DR

This paper applies a self-consistent relativistic mean-field theory to study newly observed shears bands in 60Ni, analyzing the energy spectra, transition probabilities, and the competition between configurations to understand magnetic rotation phenomena.

Contribution

It introduces a microscopic, self-consistent approach to model magnetic rotation bands in 60Ni, considering configuration competition and transition mechanisms for the first time.

Findings

Good agreement with experimental B(M1)/B(E2) ratios

B(M1) decreases with increasing spin

Reproduction of energy spectra and band crossing phenomena

Abstract

The self-consistent tilted axis cranking relativistic mean-field theory based on a point-coupling interaction has been established and applied to investigate systematically the newly observed shears bands in 60Ni. The tilted angles, deformation parameters, energy spectra, and reduced M1 and $E2$ transition probabilities have been studied in a fully microscopic and self-consistent way for various configurations and rotational frequencies. It is found the competition between the configurations and the transitions from the magnetic to the electric rotations have to be considered in order to reproduce the energy spectra as well as the band crossing phenomena. The tendency of the experimental electromagnetic transition ratios B(M1)/B(E2) is in a good agreement with the data, in particular, the B(M1) values decrease with increasing spin as expected for the shears mechanism, whose characteristics are discussed in detail by investigating the various contributions to the total angular momentum as well.