Measurement of the $W+b\bar{b}$ Cross Section at CMS

The production of a W boson in association with a pair of b quarks is studied using proton-proton collisions at $\sqrt{s}=8$ TeV in a data sample collected with the CMS experiment at the LHC corresponding to an integrated luminosity of 19.8 /fb. While previous experiments found tension between simulation and data when looking for a W boson plus at least one b quark, this study requires exactly two well separated b-tagged jets each with a transverse momentum pT$>25$ GeV and falling within the pseudorapidity range $|\eta|<2.4$. The W boson is identified by its decay to missing energy along with either an electron or a muon having pT$>30$ GeV and $|\eta|<2.1$. The cross section is computed from the unfolding of the reconstructed final-state objects to their corresponding generator-level definitions and comparisons are made between Madgraph+Pythia and MCFM using four-flavor and five-flavor schemes.