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

Time-odd mean fields (nuclear magnetism) are analyzed in the framework of covariant density functional theory (CDFT) by blocking the single-particle states with a fixed signature. It is shown that they always provide additional binding to the binding energies of odd-mass nuclei. This additional binding only weakly depends on the relativistic mean-field parametrization, reflecting good localization of the properties of time-odd mean fields in CDFT. The underlying microscopic mechanism is discussed in detail. Time-odd mean fields affect odd-even mass differences. However, our analysis suggests that the modifications of the strength of pairing correlations required to compensate for their effects are modest. In contrast, time-odd mean fields have a profound effect on the properties of odd-proton nuclei in the vicinity of the proton drip line. Their presence can modify the half-lives of proton emitters (by many orders of magnitude in light nuclei) and considerably affect the possibilities of their experimental observation.