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arXiv · 2606.04729

A note on momentum subtraction schemes for quark bilinears and semileptonic operators

P. A. Boyle·M. Bruno·M. Gorbahn·S. Jäger·C. Lehner·F. Moretti·J. Parrino
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Abstract

In this work we examine a family of regularization invariant (RI) symmetric momentum (SMOM) schemes for semi-leptonic operators. By working with chirally symmetric and massless QCD, we relate the semi-leptonic operators with their corresponding flavor-changing vector currents, whose renormalization in pure QCD is protected by the Ward identity. For the latter, we extend the original RI/SMOM scheme [Sturm et al. 2009] to a family projectors suitable to be promoted to the semi-leptonic case and demonstrate their equivalence to Ref. [Gorbahn et al. 2023], relevant in particular for the perturbative calculation of the corresponding Wilson coefficients.

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P. A. Boyle, M. Bruno, M. Gorbahn, S. Jäger, C. Lehner, F. Moretti, J. Parrino. 2026-06-03. A note on momentum subtraction schemes for quark bilinears and semileptonic operators. https://arxiv.org/abs/2606.04729

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