Measurements of inclusive W and Z cross sections in pp collisions at root s=7 TeV

Measurements of inclusive W and Z boson production cross sections in pp collisions at root s = 7 TeV are presented, based on 2 : 9 pb(-1) of data recorded by the CMS detector at the LHC. The measurements, performed in the electron and muon decay channels, are combined to give sigma(pp -> WX) x B (W -> lv) = 9.95 +/- 0.07 (stat.) +/- 0.28 (syst.) +/- 1.09 (lumi.) nb and sigma(pp -> ZX) x B (Z -> l(+)l(-)) = 0.931 +/- 0.026 (stat.) +/- 0.023 (syst.) +/- 0.102 (lumi.) nb, where l stands for either e or mu. Theoretical predictions, calculated at the next-to-next-to-leading order in QCD using recent parton distribution functions, are in agreement with the measured cross sections. Ratios of cross sections, which incur an experimental systematic uncertainty of less than 4%, are also reported. RI Mignerey, Alice/D-6623-2011; Ruiz, Alberto/E-4473-2011; Stahl, Achim/E-8846-2011; Hektor, Andi/G-1804-2011; Wulz, Claudia-Elisabeth/H-5657-2011; Chen, Jie/H-6210-2011; Bolton, Tim/A-7951-2012; Yang, Fan/B-2755-2012; Krammer, Manfred/A-6508-2010; Tinoco Mendes, Andre David/D-4314-2011; Petrushanko, Sergey/D-6880-2012; Lokhtin, Igor/D-7004-2012; Kodolova, Olga/D-7158-2012; Dudko, Lev/D-7127-2012; Katkov, Igor/E-2627-2012; Boos, Eduard/D-9748-2012; Snigirev, Alexander/D-8912-2012; Brona, Grzegorz/E-5544-2012; Servoli, Leonello/E-6766-2012; Tomei, Thiago/E-7091-2012; Novaes, Sergio/D-3532-2012; Padula, Sandra /G-3560-2012; Flix, Josep/G-5414-2012; Fruhwirth, Rudolf/H-2529-2012; Azzi, Patrizia/H-5404-2012; Torassa, Ezio/I-1788-2012