TY - JOUR AU - ATLAS Collaboration (Aad, G. et al AU - Alvarez Piqueras, D. AU - Cabrera Urban, S. AU - Castillo Gimenez, V. AU - Cerda Alberich, L. AU - Costa, M. J. AU - Fernandez Martinez, P. AU - Ferrer, A. AU - Fiorini, L. AU - Fuster, J. AU - Garcia, C. AU - Garcia Navarro, J. E. AU - Gonzalez de la Hoz, S. AU - Hernandez Jimenez, Y. AU - Higon-Rodriguez, E. AU - Irles Quiles, A. AU - Jimenez Pena, J. AU - Kaci, M. AU - King, M. AU - Lacasta, C. AU - Lacuesta, V. R. AU - Marti-Garcia, S. AU - Mitsou, V. A. AU - Pedraza Lopez, S. AU - Perez Garcia-Estañ, M. T. AU - Romero Adam, E. AU - Ros, E. AU - Salt, J. AU - Sanchez Martinez, V. AU - Soldevila, U. AU - Sanchez, J. AU - Valero, A. AU - Valls Ferrer, J. A. AU - Vos, M. PY - 2016 DA - 2016// TI - Evidence for single top-quark production in the s-channel in proton-proton collisions at root s=8 TeV with the ATLAS detector using the Matrix Element Method T2 - Phys. Lett. B JO - Physics Letters B SP - 228 EP - 246 VL - 756 PB - Elsevier Science Bv AB - This Letter presents evidence for single top-quark production in the s-channel using proton-proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS detector at the CERN Large Hadron Collider. The analysis is performed on events containing one isolated electron or muon, large missing transverse momentum and exactly two b-tagged jets in the final state. The analysed data set corresponds to an integrated luminosity of 20.3 fb(-1). The signal is extracted using a maximum-likelihood fit of a discriminant which is based on the matrix element method and optimized in order to separate single-top-quark s-channel events from the main background contributions, which are top-quark pair production and W boson production in association with heavy-flavour jets. The measurement leads to an observed signal significance of 3.2 standard deviations and a measured cross-section of sigma s = 4.8 +/- 0.8(stat.)(-1.3)(+1.6)(syst.) pb, which is consistent with the Standard Model expectation. The expected significance for the analysis is 3.9 standard deviations. SN - 0370-2693 UR - http://arxiv.org/abs/1511.05980 UR - https://doi.org/10.1016/j.physletb.2016.03.017 DO - 10.1016/j.physletb.2016.03.017 LA - English N1 - WOS:000373569200035 ID - ATLASCollaborationAad_etal2016 ER -