Measurement of the ppbar -> W+b+X production cross section at \sqrt{s}=1.96 TeV

Abstract

We present a measurement of the cross section for $W$ boson production in association with at least one {$b$-quark} jet in proton-antiproton collisions. The measurement is made using data corresponding to an integrated luminosity of 6.1\ifb recorded with the D0 detector at the Fermilab Tevatron \ppbar Collider at $\sqrt{s}=1.96$ TeV. We measure an inclusive cross section of {$σ(W \sim(\toμν) + b + X) = 1.04 \pm 0.05\thinspace$(stat.) $\pm 0.12 \thinspace$(syst.) pb} and $σ(W (\to eν) + b + X) = 1.00$ \pm 0.04 \thinspace$(stat.) $\pm 0.12 \thinspace$(syst.) pb in the phase space defined by $p_T^ν> 25$ GeV, $p_T^{\text{$b$-jet}}>20$ GeV, $|η^{\text{$b$-jet}}|<1.1$, and a muon (electron) with $p_T^\ell>20$ GeV and $|η^μ|<1.7$ ($|η^e|<1.1$ or $1.5<|η^e|<2.5$). The combined result per lepton family is $σ(W (\to \ell ν) + b + X) = 1.05$ $\pm 0.12 \thinspace$(stat.+syst.) for $|η^\ell|<1.7$. The results are in agreement with predictions from next-to-leading order QCD calculations using \textsc{mcfm}, $σ(W+b)\cdot {\cal B}(W \to \ell ν)= 1.34 ^{+0.41}_{-0.34}\thinspace(\textrm{syst.})$, and also with predictions from the \textsc{sherpa} and \textsc{madgraph} Monte Carlo event generators.