- Aad, G;
- Abbott, B;
- Abdallah, J;
- Abdelalim, AA;
- Abdesselam, A;
- Abdinov, O;
- Abi, B;
- Abolins, M;
- Abramowicz, H;
- Abreu, H;
- Acerbi, E;
- Acharya, BS;
- Adams, DL;
- Addy, TN;
- Adelman, J;
- Aderholz, M;
- Adomeit, S;
- Adragna, P;
- Adye, T;
- Aefsky, S;
- Aguilar-Saavedra, JA;
- Aharrouche, M;
- Ahlen, SP;
- Ahles, F;
- Ahmad, A;
- Ahsan, M;
- Aielli, G;
- Akdogan, T;
- Åkesson, TPA;
- Akimoto, G;
- Akimov, AV;
- Akiyama, A;
- Alam, MS;
- Alam, MA;
- Albert, J;
- Albrand, S;
- Aleksa, M;
- Aleksandrov, IN;
- Alessandria, F;
- Alexa, C;
- Alexander, G;
- Alexandre, G;
- Alexopoulos, T;
- Alhroob, M;
- Aliev, M;
- Alimonti, G;
- Alison, J;
- Aliyev, M;
- Allport, PP;
- Allwood-Spiers, SE;
- Almond, J;
- Aloisio, A;
- Alon, R;
- Alonso, A;
- Alviggi, MG;
- Amako, K;
- Amaral, P;
- Amelung, C;
- Ammosov, VV;
- Amorim, A;
- Amorós, G;
- Amram, N;
- Anastopoulos, C;
- Ancu, LS;
- Andari, N;
- Andeen, T;
- Anders, CF;
- Anders, G;
- Anderson, KJ;
- Andreazza, A;
- Andrei, V;
- Andrieux, ML;
- Anduaga, XS;
- Angerami, A;
- Anghinolfi, F;
- Anjos, N;
- Annovi, A;
- Antonaki, A;
- Antonelli, M;
- Antonov, A;
- Antos, J;
- Anulli, F;
- Aoun, S;
- Aperio Bella, L;
- Apolle, R;
- Arabidze, G;
- Aracena, I;
- Arai, Y;
- Arce, ATH;
- Archambault, JP;
- Arfaoui, S;
- Arguin, JF;
- Arik, E;
- Arik, M;
- Armbruster, AJ;
- Arnaez, O;
- Arnault, C;
- Artamonov, A;
- Artoni, G;
- Arutinov, D
A measurement is presented of the cross section for the production of a W boson with one or two jets, of which at least one must be a b-jet, in pp collisions at √s = 7 TeV. Production via top decay is not included in the signal definition. The measurement is based on 35 pb-1 of data collected with the ATLAS detector at the LHC. The W + b-jet cross section is defined for jets reconstructed with the antikt clustering algorithm with transverse momentum above 25 GeV and rapidity within ±2.1. The b-jets are identified by reconstructing secondary vertices. The fiducial cross section is measured both for the electron and muon decay channel of the W boson and is found to be 10.2 ± 1.9(stat) ± 2.6(syst) pb for one lepton flavour. The results are compared with next-to-leading order QCD calculations, which predict a cross section smaller than, though consistent with, the measured value.