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arXiv · 2507.01670

Precision determination of $α_\text{s}$ from Dijet Cross Sections in the Multi-TeV Range

João Pires
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Abstract

In this talk we present a determination of the strong coupling constant $α_\text{s}$ and its energy-scale dependence based on a next-to-next-to-leading order (NNLO) QCD analysis of dijet production. Using the invariant mass of the dijet system to probe $α_\text{s}$ at different scales, we extract a value of $α_\text{s}(m_\text{Z})=0.1178 \pm 0.0022$ from LHC dijet data. The combination of various LHC datasets significantly extends the precision and scale reach of the analysis, enabling the first determination of $α_\text{s}$ up to 7 TeV. By incorporating dijet cross sections from HERA, we further probe $α_\text{s}$ at smaller scales, covering a kinematic range of more than three orders of magnitude. Our results are in excellent agreement with QCD predictions based on the renormalization group equation, providing a stringent test of the running of the strong coupling across a wide energy range.

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João Pires. 2025-07-02. Precision determination of $α_\text{s}$ from Dijet Cross Sections in the Multi-TeV Range. https://arxiv.org/abs/2507.01670

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