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arXiv · 2203.14754

Non-perturbative renormalization of the QCD flavour-singlet local vector current

Matteo Bresciani·Mattia Dalla Brida·Leonardo Giusti·Michele Pepe·Federico Rapuano
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Abstract

We compute non-perturbatively the renormalization constant of the flavour-singlet local vector current $Z_V$ in lattice QCD with 3 massless flavours. Gluons are discretized by the Wilson plaquette action while quarks by the O($a$)-improved Wilson--Dirac operator. The constant $Z_V$ is fixed by comparing the expectation values (1-point functions) of the conserved and local vector currents at finite temperature in the presence of shifted boundary conditions and at non-zero imaginary chemical potential. Monte Carlo simulations with a moderate computational cost allow us to obtain $Z_V$ with an accuracy of about 8\textperthousand\, for values of the inverse bare coupling constant $β=6/g_0^2$ in the range $5.3 \leq β\leq 11.5$.

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Matteo Bresciani, Mattia Dalla Brida, Leonardo Giusti, Michele Pepe, Federico Rapuano. 2022-11-21. Non-perturbative renormalization of the QCD flavour-singlet local vector current. https://doi.org/10.1016/j.physletb.2022.137579

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