Measurement of the cross-section for W boson production in association with b-jets in pp collisions at √s=7 TeV with the ATLAS detector

This paper reports a measurement of the W+b-jets (W+b+X and W+bb +X) production cross-section in proton-proton collisions at a centre-of-mass energy of 7 TeV at the LHC. These results are based on data corresponding to an integrated luminosity of 4:6 fb-1, collected with the ATLAS detector. Cross-sections are presented as a function of jet multiplicity and of the transverse momentum of the leading b-jet for both the muon and electron decay modes of the W boson. The W+b-jets cross-section, corrected for all known detector eects, is quoted in a limited kinematic range. Combining the muon and electron channels, the ducial cross-section for W+b-jets is measured to be 7.1 0.5 (stat) 1.4 (syst) pb, consistent with the next-to-leading order QCD prediction, corrected for non-perturbative and double-parton interactions (DPI) contributions, of 4:700:09 (stat) +0:60 -0:49 (scale) 0:06 (PDF) 0:16 (non-pert) +0:52 -0:38 (DPI) pb.