One-loop matching for quark dipole operators in a gradient-flow scheme

Abstract

The quark chromoelectric dipole (qCEDM) operator is a CP-violating operator describing, at hadronic energies, beyond-the-standard-model contributions to the electric dipole moment of particles with nonzero spin. In this paper we define renormalized dipole operators in a regularization-independent scheme using the gradient flow, and we perform the matching at one loop in perturbation theory to renormalized operators of the same and lower dimension in the more familiar MS scheme. We also determine the matching coefficients for the quark chromomagnetic dipole operator (qCMDM), which contributes, for example, to matrix elements relevant to CP-violating and CP-conserving kaon decays. The calculation provides a basis for future lattice QCD computations of hadronic matrix elements of the qCEDM and qCMDM operators.

24 pages, 4 figures Published version: added references, added discussion of nonperturbative effects in section 5.2. all results unchanged

References in corpus (6)

• Measurement of the permanent electric dipole moment of the neutron
• Perturbative analysis of the gradient flow in non-abelian gauge theories
• The Nucleon Electric Dipole Form Factor From Dimension-Six Time-Reversal Violation
• The Electric Dipole Form Factor of the Nucleon in Chiral Perturbation Theory to Sub-leading Order
• Neutron Electric Dipole Moment Induced by the Strangeness Revisited
• QCD Static Force in Gradient Flow