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arXiv · 1912.06001

Non-perturbative renormalization by decoupling

Mattia Dalla Brida·Roman Höllwieser·Francesco Knechtli·Tomasz Korzec·Alberto Ramos·Rainer Sommer
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Abstract

We propose a new strategy for the determination of the QCD coupling. It relies on a coupling computed in QCD with $N_{\rm f} \geq 3$ degenerate heavy quarks at a low energy scale $\mu_{\rm dec}$, together with a non-perturbative determination of the ratio $\Lambda/\mu_{\rm dec}$ in the pure gauge theory. We explore this idea using a finite volume renormalization scheme for the case of $N_{\rm f} = 3$ QCD, demonstrating that a precise value of the strong coupling $\alpha_s$ can be obtained. The idea is quite general and can be applied to solve other renormalization problems, using finite or infinite volume intermediate renormalization schemes.

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Mattia Dalla Brida, Roman Höllwieser, Francesco Knechtli, Tomasz Korzec, Alberto Ramos, Rainer Sommer. 2019-12-12. Non-perturbative renormalization by decoupling. https://doi.org/10.1016/j.physletb.2020.135571

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