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Updated: Sep 12, 2025

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Precise Determination of the Strong Coupling Constant from Dijet Cross Sections up to the Multi-TeV Range
Fazila Ahmadova1,2, Daniel Britzger1, Xuan Chen3
1Max-Planck-Institut für Physik, Boltzmannstraße 8, 85748 Garching, Germany.
None:
We determine the value of the strong coupling α_{s} and study its running over a wide range of scales as probed by the dijet production process at hadron colliders, based on a next-to-next-to-leading-order QCD analysis of LHC dijet data. From a large subset of these data a value of α_{s}(m_{Z})=0.1178±0.0022 is obtained for the strong coupling at the scale of the Z-boson mass m_{Z}, using the invariant mass of the dijet system to select the scale where α_{s} is probed. The combination of different datasets enhances the reach and precision of the analysis in the multi-TeV range and allows for the first determination of α_{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 toward 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.
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