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arXiv · 2111.12120

Renormalization constants of quark bilinear operators in QCD with dynamical up, down, strange and charm quarks

Matteo Di Carlo·Martha Constantinou·Petros Dimopoulos·Roberto Frezzotti
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Abstract

We present preliminary results of a calculation of the QCD renormalization constants (RCs) for quark bilinear operators, evaluated non-perturbatively on the lattice in the RI'-MOM scheme. The calculation is performed by using dedicated ensembles with $N_f=4$ degenerate dynamical twisted mass (clover) fermions and the Iwasaki gauge action. A detailed analysis is reported, with emphasis on the control or subtraction of the hadronic contaminations occurring in the lattice estimators of RCs and a check of proper scaling with $a^2$ of the final results. Such a careful study of systematic errors is the counterpart of the high statistical precision reached by current calculations of RCs in the RI'-MOM scheme and is important in order to quote accurate results in phenomenological applications, such as the computation of quark masses.

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Matteo Di Carlo, Martha Constantinou, Petros Dimopoulos, Roberto Frezzotti. 2021-11-23. Renormalization constants of quark bilinear operators in QCD with dynamical up, down, strange and charm quarks. https://arxiv.org/abs/2111.12120

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