One-loop matching of improved four-fermion staggered operators with an improved gluon action

Abstract

We present results for one-loop matching factors of four-fermion operators composed of HYP-smeared staggered fermions. We generalize previous calculations by using the tree-level improved Symanzik gauge action. These results are needed for our companion numerical calculation of $B_K$ and related matrix elements. We find that the impact on one-loop matching factors of using the improved gluon action is much smaller than that from the use of either HYP smearing or mean-field improvement. The one-loop coefficients for mean-field improved, HYP-smeared operators with the Symanzik gauge action have a maximum magnitude of $O(1)\times {\alpha }_s$, indicating that perturbation theory is reasonably convergent.

11 pages, 16 figures, references are updated

References in corpus (4)

• Staggered Chiral Perturbation Theory and the Fourth-Root Trick
• Renormalization-group analysis of the validity of staggered-fermion QCD with the fourth-root recipe
• $B_K$ using HYP-smeared staggered fermions in $N_f=2+1$ unquenched QCD
• Effective field theories for QCD with rooted staggered fermions