%0 Journal Article %T Measurements of fiducial cross-sections for t(t)over-bar production with one or two additional b-jets in pp collisions at root s=8 TeV using the ATLAS detector %A ATLAS Collaboration (Aad, G. et al %A Alvarez Piqueras, D. %A Cabrera Urban, S. %A Castillo Gimenez, V. %A Costa, M. J. %A Fernandez Martinez, P. %A Ferrer, A. %A Fiorini, L. %A Fuster, J. %A Garcia, C. %A Garcia Navarro, J. E. %A Gonzalez de la Hoz, S. %A Hernandez Jimenez, Y. %A Higon-Rodriguez, E. %A Irles Quiles, A. %A Jimenez Pena, J. %A Kaci, M. %A King, M. %A Lacasta, C. %A Lacuesta, V. R. %A Marti-Garcia, S. %A Mitsou, V. A. %A Pedraza Lopez, S. %A Perez Garcia-Estañ, M. T. %A Romero Adam, E. %A Ros, E. %A Salt, J. %A Sanchez Martinez, V. %A Soldevila, U. %A Sanchez, J. %A Valero, A. %A Valls Ferrer, J. A. %A Vos, M. %J European Physical Journal C %D 2016 %V 76 %N 1 %I Springer %@ 1434-6044 %G English %F ATLASCollaborationAad_etal2016 %O WOS:000370645300001 %O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=2563), last updated on Thu, 28 Jul 2016 12:01:58 +0000 %X Fiducial cross-sections for t (t) over bar production with one or two additional b-jets are reported, using an integrated luminosity of 20.3 fb(-1) of proton-proton collisions at a centre-of-mass energy of 8 TeV at the Large Hadron Collider, collected with the ATLAS detector. The cross-section times branching ratio for t (t) over bar events with at least one additional b-jet is measured to be 950 +/- 70 (stat.)(-190)(+240) (syst.) fb in the lepton-plus-jets channel and 50 +/- 10 (stat.)(-10)(+15) (syst.) fb in the e μchannel. The cross-section times branching ratio for events with at least two additional b-jets is measured to be 19.3 +/- 3.5 (stat.) +/- 5.7 (syst.) fb in the dilepton channel (e mu, μmu, and ee) using a method based on tight selection criteria, and 13.5 +/- 3.3 (stat.) +/- 3.6 (syst.) fb using a looser selection that allows the background normalisation to be extracted from data. The latter method also measures a value of 1.30 +/- 0.33 (stat.) +/- 0.28 (syst.)% for the ratio of t (t) over bar production with two additional b-jets to t (t) over bar production with any two additional jets. All measurements are in good agreement with recent theory predictions. %R 10.1140/epjc/s10052-015-3852-4 %U http://arxiv.org/abs/1508.06868 %U https://doi.org/10.1140/epjc/s10052-015-3852-4 %P 11-37pp