Journal of High Energy Physics (Apr 2022)

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

  • Emanuele Mereghetti,
  • Christopher J. Monahan,
  • Matthew D. Rizik,
  • Andrea Shindler,
  • Peter Stoffer

DOI
https://doi.org/10.1007/JHEP04(2022)050
Journal volume & issue
Vol. 2022, no. 4
pp. 1 – 30

Abstract

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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 chromo-magnetic 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.

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