W+Heavy Flavour Jet Measurements at CMS

The production of W bosons in association with b quarks is studied using proton-proton collisions at p s = 7 TeV in a data sample collected with the CMS experiment at the LHC corresponding to an integrated luminosity of 5 : 0 fb 1 . The W + b ̄ b events are selected in the W ! mn decay mode by requiring a muon with transverse momentum p T > 25 GeV and pseudorapidity j h j < 2 : 1, and exactly two b-tagged jets with p T > 25 GeV and j h j < 2 : 4. The measured W + b ̄ b production cross section in the fiducial volume, calculated at the level of final-state particles, is 0 : 53 0 : 05 ( stat. ) 0 : 09 ( syst. ) 0 : 06 ( th. ) 0 : 01 ( lum. ) pb, in agreement with the standard model prediction. In addition, kinematic distributions of the W + b ̄ b system are measured and found to be in agreement with the predictions of a simulation using MADGRAPH and PYTHIA