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arXiv · 2603.21059

Towards determination of the strong coupling $\alpha_s(m_Z)$ from four-flavor lattice QCD using the continuous $\beta$-function method

Yash Mandlecha·Alexei Bazavov·Akhil Chauhan·Mingwei Dai·Carleton DeTar·Aida El-Khadra·Steven Gottlieb·Anna Hasenfratz·Leon Hostetler·Andreas S. Kronfeld·Ethan T. Neil·Curtis T. Peterson·James Simone
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Abstract

The precise value of the strong coupling $\alpha_s(m_{Z})$ at the $Z$-boson mass $m_{Z}$ is essential for high-energy phenomenology and precision tests of quantum chromodynamics (QCD). We present the status of a program targeting a $\sim 0.3\%$ determination of $\alpha_s(m_{Z})$ using the renormalization group $\beta$-function in the infinite volume gradient flow scheme based on lattice QCD simulations of degenerate four-flavor highly improved staggered quark (HISQ) ensembles. In particular, we analyze both tree-level cutoff effects and finite-mass effects. We also outline the next steps of the analysis, including the infinite-volume and continuum extrapolations required for a precise determination of $\alpha_s(m_Z)$.

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Yash Mandlecha, Alexei Bazavov, Akhil Chauhan, Mingwei Dai, Carleton DeTar, Aida El-Khadra, Steven Gottlieb, Anna Hasenfratz, Leon Hostetler, Andreas S. Kronfeld, Ethan T. Neil, Curtis T. Peterson, James Simone. 2026-03-22. Towards determination of the strong coupling $\alpha_s(m_Z)$ from four-flavor lattice QCD using the continuous $\beta$-function method. https://arxiv.org/abs/2603.21059

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