Time-odd mean fields in covariant density functional theory: Rotating systems

TL;DR

This paper investigates the influence of time-odd mean fields, or nuclear magnetism, on the moments of inertia and band crossing phenomena in rotating nuclei within covariant density functional theory, revealing their significant effects and weak parametrization dependence.

Contribution

It provides a systematic analysis of how time-odd mean fields affect rotational properties and band crossing features in nuclei, with detailed insights into their microscopic origins and phenomenological implications.

Findings

Time-odd mean fields significantly affect moments of inertia.

Nuclear magnetism alters band crossing features.

Moments of inertia in normal-deformed nuclei deviate from rigid body values.

Abstract

Time-odd mean fields (nuclear magnetism) and their impact on physical observables in rotating nuclei are studied in the framework of covariant density functional theory (CDFT). It is shown that they have profound effect on the dynamic and kinematic moments of inertia. Particle number, configuration and rotational frequency dependences of their impact on the moments of inertia have been analysed in a systematic way. Nuclear magnetism can also considerably modify the band crossing features such as crossing frequencies and the properties of the kinematic and dynamic moments of inertia in the band crossing region. The impact of time-odd mean fields on the moments of inertia in the regions away from band crossing only weakly depends on the relativistic mean field parametrization, reflecting good localization of the properties of time-odd mean fields in CDFT. The moments of inertia of normal-deformed nuclei considerably deviate from the rigid body value. On the contrary, superdeformed and hyperdeformed nuclei have the moments of inertia which are close to rigid body value. The structure of the currents in rotating frame, their microscopic origin and the relations to the moments of inertia have been systematically analysed. The phenomenon of signature separation in odd-odd nuclei, induced by time-odd mean fields, has been analysed in detail.