nEDM from the theta-term and chromoEDM operators

TL;DR

This paper advances the calculation of nucleon electric dipole moments by analyzing the effects of excited state contamination, operator mixing, and presenting preliminary lattice results for the theta-term and chromoEDM operators.

Contribution

It extends previous work to include the quark chromoEDM operator and examines operator mixing effects, providing new insights into systematic uncertainties.

Findings

Excited state contaminations significantly affect EDM calculations.

Operator mixing impacts the lattice results for chromoEDM.

Preliminary lattice results for the theta-term are presented.

Abstract

In a previous work, we showed that unresolved excited state contaminations provide a major source of systematic uncertainty in the calculation of the nucleon electric dipole moment due to the QCD topological term theta. Here we extend the calculation to the quark chromo-electric dipole moment operator (qcEDM). We also show quantitatively the impact of the mixing of the qcEDM with lower-dimensional operators on the lattice. Finally, we present preliminary results from a unitary clover-on-clover calculation for the QCD topological term.