Recent QCD results from ATLAS

The ATLAS collaboration has performed studies of a wide range of QCD phe-\nnomena. Recent soft-QCD measurements include studies of hadronic event shapes and\ndouble-parton scattering. Differential measurements of inclusive-jet production provide\nstringent tests of higher-order QCD predictions and provide input for the determination\nof the parton density functions. Jet-multiplicity ratios are sensitive to the strong cou-\npling constant and have reduced sensitivity to the uncertainties due to parton distribution\nfunctions. Measurements of the inclusive isolated-photon, photon plus jet and diphoton\ndifferential cross sections provide a direct probe of short-distance physics, complemen-\ntary to that from measurements of jets or vector-bosons, and are sensitive to the gluon\ndensity of the proton.