Proton PDFs constraints from measurements using the ATLAS experiment

High-precision measurements of Standard Model (SM) processes provide information on different aspects contributing to the process, such as parton distribution functions (PDFs), and comparisons with the current precision reached theoretically on the calculations of the cross sections of such processes. This document describes ATLAS measurements, performed at different centre-of-mass energies, of vector boson ( W and Z ) cross sections and cross-section ratios. It also discusses measurements of ratios of Z -boson and top -quark pair production cross sections, which provide important information on the proton PDFs. Finally, a measurement involving the di-lepton decay channel of top -quark pairs at 8 TeV is presented, because of its direct sensitivity to the gluon PDF.