Scale setting and strong coupling determination in the gradient flow scheme for 2+1 flavor lattice QCD

Year: 2026

Type: article

Abstract: A bstract We report on the determination of the gradient flow scales in N f = 2 + 1 QCD using highly improved staggered quark (HISQ) ensembles generated by the HotQCD Collaboration for bare gauge couplings ranging from β = 6 . 423 to 8 . 400. Using bottomonium splittings, kaon decay constant, the decay constant of unmixed η s meson and the ϕ meson mass we obtained the values of the gradient flow scales in physical units, $$ \sqrt{t_0} $$ t 0 = 0.14446(76) fm and w 0 = 0.17429(83) fm. Using the same physical inputs we revisit the determination of the potential r 1 scale and find r 1 = 0 . 3118(26) fm. As a byproduct of our study we obtain the running of the gauge coupling in the gradient flow scheme. We find that within the uncertainties the running of the gradient flow coupling obtained on the lattice is compatible with the perturbative results up to flow radius $$ \sqrt{8{\tau}_F} $$ 8 τ F = 0.15 fm.

Source: Journal of High Energy Physics

DOI: 10.1007/jhep10(2026)039

Authors: Rasmus Norman Larsen, Swagato Mukherjee, Peter Petreczky, Hai-Tao Shu, Johannes Heinrich Weber

Institutions: Bielefeld University, Brookhaven National Laboratory, Central China Normal University, Technische Universität Darmstadt, Humboldt-Universität zu Berlin

Language: English

Topic: Quantum Chromodynamics and Particle Interactions

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: diamond

Funders: U.S. Department of Energy, National Energy Research Scientific Computing Center, Deutsche Forschungsgemeinschaft, Ministerium für Kultur und Wissenschaft des Landes Nordrhein-Westfalen, Office of Science, Nuclear Physics, Lawrence Berkeley National Laboratory

OpenAlex ID: W4407569696