Measurement of the W and Z inclusive production cross sections at sqrts=7 TeV with the CMS experiment at the LHC

We present the measurements of inclusive W and Z production cross sections in electron and muon decay channels at $\sqrt{s} = 7~$TeV, obtained using $36~\text{pb}^{-1}$ of pp collisions in the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC). The measured inclusive cross sections are sigma(pp--$>$WX)xBF(W--$>$ln) = 10.31 +/- 0.02(stat.) +/- 0.09(syst.) +/- 0.10(th.) +/- 0.41(lumi.) nb and sigma(pp--$>$ZX)xBF(Z--$>$ l+ l- ) = 0.975 +/- 0.007(stat.) +/- 0.007(syst.) +/- 0.018(th.) +/- 0.039(lumi.) nb limited to the di-lepton invariant mass range [60, 120] GeV. The luminosity-independent cross section ratios are ( sigma(pp--$>$WX)xBF(W--$>$ln) ) / ( sigma(pp--$>$ZX)xBF(Z--$>$ l+ l- ) ) = 10.54 +/- 0.07(stat.) +/- 0.08(syst.) +/- 0.16(th.) and ( sigma(pp--$>$W+ X)xBF(W+ --$>$ l+ n) ) / ( sigma(pp--$>$W- X)xBF(W- --$>$ l- n) ) = 1.421 +/- 0.006(stat.) +/- 0.014(syst.) +/- 0.030(th.). The measured values agree with NNLO QCD cross section calculations and current parton distribution functions.