Parity and time-reversal symmetry violation in diatomic molecules: LaO, LaS and LuO

TL;DR

This study calculates the enhancement of parity and time-reversal symmetry violations in LaO, LaS, and LuO molecules using relativistic coupled cluster methods, providing insights into fundamental symmetry-breaking interactions.

Contribution

It presents the first systematic calculation of P, T-violating effects in these molecules with estimated uncertainties, advancing the understanding of symmetry violations in heavy diatomic molecules.

Findings

Calculated enhancement factors for P, T-violation in LaO, LaS, LuO

Estimated total uncertainty of about 7% in the calculations

Linked molecular effects to higher-energy P, T-violating interactions

Abstract

The violation of parity (P) and time-reversal (T) symmetry is enhanced in the LaS, LaO and LuO molecules due to the existence of states of opposite parity with small energy differences and the presence of heavy nuclei. We calculate the molecular enhancement for the P, T-violating electron electric dipole moment ($W_{\mathrm{d}}$), scalar-pseudoscalar nucleon-electron interaction ($W_{\mathrm{s}}$), nuclear magnetic quadrupole moment ($W_{\mathrm{M}}$), and for the nuclear spin-dependent P-violating anapole moment ($W_{\mathrm{A}}$). We use the relativistic 4-components coupled cluster method and perform a systematic study to estimate the associated uncertainties in our approach. We find that the individual contribution of each computational parameter to the total uncertainty in a system is approximately the same for all the calculated enhancement factors, summing up to a total uncertainty of $\sim7$\%. We discuss the energy shifts and matrix elements associated with the calculated molecular enhancement factors and relate them to higher-energy P- and P, T- violating interactions.