$W$ and $Z$ boson production in 5.02 TeV $pp$ and $p$+Pb collisions with the ATLAS detector

This proceeding reports the ATLAS results of measuring vector boson production in pp and p +Pb collisions at the center-of-mass energy of 5.02 TeV per nucleon. Z bosons are reconstructed via leptonic decays and results are presented as a function of Z -boson rapidity. W bosons are identified by measuring leptons coming from W decays and the results are presented as a function of lepton pseudorapidity. In pp collisions Z boson cross section in |yZ|<2.5 is 590±9(stat.)±12(syst.)±32(lumi.) pb . In p +Pb system kinematic distributions of W and Z bosons are compared to models based on NLO and NNLO QCD calculations using different PDF sets. Using PDF modification shows better agreement of the model and the data. Measurements done in different centrality intervals show that the PDF modification in p +Pb may have centrality dependence.