Standard Model Soft and Hard QCD at ATLAS and CMS

Abstract

Quantum Chromodynamics (QCD) is explored at the Large Hadron Collider (LHC) over a wide range of energy scales, from soft hadronic interactions to hard parton scattering. This contribution presents a selection of recent measurements from the ATLAS and CMS experiments probing QCD in proton--proton collisions at the LHC. The results span a broad range of momentum scales, from studies of charged-particle event-shape observables in minimum-bias events, which are sensitive to soft QCD dynamics and hadronisation, to measurements of inclusive di-jet production that provide stringent tests of perturbative QCD. Recent studies of double-parton scattering in same-sign $WW$ production are also discussed, offering new insight into multi-parton interactions inside the proton. Finally, the capabilities of the forward proton detectors operated by the ATLAS and CMS collaborations are briefly reviewed, highlighting their contribution to the LHC physics programme through measurements of diffractive and photon-induced processes.