Dipole resonances and the nuclear Schiff moment

TL;DR

This paper investigates how low-lying nuclear dipole resonances can significantly enhance the nuclear Schiff moment, which is crucial for understanding atomic electric dipole moments and fundamental symmetry violations.

Contribution

It introduces an additional contribution to the Schiff moment from nuclear dipole resonances, highlighting potential enhancements due to collective effects.

Findings

Low-lying nuclear dipole resonances contribute significantly to the Schiff moment.

The resonance contribution can be comparable to single-particle effects.

Collective resonances can further enhance the Schiff moment.

Abstract

The nuclear Schiff moment creates a mechanism of transfer of the violation of parity and time-reversal invariance by weak interaction in nuclei into the atomic electric dipole moment. We point out an additional contribution to the Schiff moment generated by the mixing of single-particle states through the low-lying nuclear dipole resonances. An estimate shows that this contribution is by order of magnitude comparable to single-particle contributions and can be enhanced if the low-lying resonance has collective nature.