Off Mass Shell Effects in Hadron Electric Dipole Moments

TL;DR

This paper investigates how off-shell effects of quark operators influence the calculation of hadronic electric dipole moments, revealing differences that could impact theoretical predictions.

Contribution

It highlights the non-equivalence of certain quark operators off the mass shell and explores their impact on hadronic electric moments.

Findings

Off-shell operators differ from on-shell counterparts.

Off-shell effects modify contributions to hadronic electric moments.

Potential implications for precision calculations in hadron physics.

Abstract

We note that off the quark mass shell the operators $(p_i+p_f)_\mu\gamma_5$ and $i\sigma_{\mu\nu}(p_i -p_f)^\nu\gamma_5$, both of which reduce to $-\vec{\sigma}\cdot\vec{E}$ in the non-relativistic limit, are no longer identical. In this paper we explore the effects of this difference in the contribution of these quark electric moments to hadronic electric moments.