Precise Determination of the Strong Coupling Constant from Dijet Cross Sections up to the Multi-TeV Range

Abstract

We determine the value of the strong coupling $\hat{I}{\pm }_{\text{s}}$ and study its running over a wide range of scales as probed by the dijet production process at hadron colliders, based on an NNLO QCD analysis of LHC dijet data. From a large subset of these data a value of $\hat{I}{\pm }_{\text{s}}(m_{\text{Z}})=0.1178\pm 0.0022$ is obtained for the strong coupling at the scale of the Z-boson mass $m_{\text{Z}}$, using the invariant mass of the dijet system to select the scale where $\hat{I}{\pm }_{\text{s}}$ is probed. The combination of different data sets enhances the reach and precision of the analysis in the mutli-TeV range and allows for the first determination of $\hat{I}{\pm }_{\text{s}}$ up to scales of 7 TeV. Complementing the LHC data with dijet cross sections measured at the HERA electron-proton collider, the kinematic range is extended to test the running of the strong coupling towards smaller scales. Our results exhibit excellent agreement with predictions based on the renormalization group equation of QCD, and represent a comprehensive test of the asymptotic behavior of QCD, spanning more than three orders of magnitude in energy scale.

5 pages, 3 figures, appendix with 2 pages, supplementary material with 3 pages and 3 figures. To be published in Phys$.$Rev$.$Lett$.$