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arXiv · 2311.15796

Mass effects on the QCD $\beta$-function

Marios Costa·Demetrianos Gavriel·Haralambos Panagopoulos·Gregoris Spanoudes
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Abstract

In this study we present lattice results on the QCD $\beta$-function in the presence of quark masses. The $\beta$-function is calculated to three loops in perturbation theory and for improved lattice actions; it is extracted from the renormalization of the coupling constant $Z_g$. The background field method is used to compute $Z_g$, where it is simply related to the background gluon field renormalization constant $Z_A$. We focus on the quark mass effects in the background gluon propagator; the dependence of the QCD $\beta$-function on the number of colors $N_c$, the number of fermionic flavors $N_f$ and the quark masses, is shown explicitly. The perturbative results of the QCD $\beta$-function will be applied to the precise determination of the strong coupling constant, calculated by Monte Carlo simulations removing the mass effects from the nonperturbative Green's functions.

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Marios Costa, Demetrianos Gavriel, Haralambos Panagopoulos, Gregoris Spanoudes. 2023-11-27. Mass effects on the QCD $\beta$-function. https://arxiv.org/abs/2311.15796

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