%0 Journal Article %T Search for t(t)over-bar resonances in the lepton plus jets final state with ATLAS using 4.7 fb(-1) of pp collisions at root s=7 TeV %A ATLAS Collaboration (Aad, G. et al %A Cabrera Urban, S. %A Castillo Gimenez, V. %A Costa, M. J. %A Fassi, F. %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 Kaci, M. %A Lacasta, C. %A Lacuesta, V. R. %A March, L. %A Marti-Garcia, S. %A Miñano, M. %A Mitsou, V. A. %A Moles-Valls, R. %A Moreno Llacer, M. %A Oliver Garcia, E. %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 Torro Pastor, E. %A Valero, A. %A Valladolid Gallego, E. %A Valls Ferrer, J. A. %A Villaplana Perez, M. %A Vos, M. %J Physical Review D %D 2013 %V 88 %N 1 %I Amer Physical Soc %@ 1550-7998 %G English %F ATLASCollaborationAad_etal2013 %O WOS:000322145600002 %O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=1491), last updated on Wed, 28 Aug 2013 12:23:58 +0000 %X A search for new particles that decay into top quark pairs (t (t) over bar) is performed with the ATLAS experiment at the LHC using an integrated luminosity of 4.7 fb(-1) of proton-proton (pp) collision data collected at a center-of-mass energy root s = 7 TeV. In the t (t) over bar) -> WbWb decay, the lepton plus jets final state is used, where one W boson decays leptonically and the other hadronically. The t (t) over bar) system is reconstructed using both small-radius and large-radius jets, the latter being supplemented by a jet substructure analysis. A search for local excesses in the number of data events compared to the Standard Model expectation in the t (t) over bar) invariant mass spectrum is performed. No evidence for a t (t) over bar) resonance is found and 95% credibility-level limits on the production rate are determined for massive states predicted in two benchmark models. The upper limits on the cross section times branching ratio of a narrow Z' resonance range from 5.1 pb for a boson mass of 0.5 TeV to 0.03 pb for a mass of 3 TeV. A narrow leptophobic topcolor Z' resonance with a mass below 1.74 TeV is excluded. Limits are also derived for a broad color-octet resonance with m 15.3%. A Kaluza-Klein excitation of the gluon in a Randall-Sundrum model is excluded for masses below 2.07 TeV. %R 10.1103/PhysRevD.88.012004 %U http://arxiv.org/abs/arXiv:1305.2756 %U https://doi.org/10.1103/PhysRevD.88.012004 %P 012004-28pp