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 √s=7 TeV

被引:45
作者
Aad, G. [73 ]
Abajyan, T. [33 ]
Abbott, B. [152 ]
Abdallah, J. [16 ,17 ,18 ]
Khalek, S. Abdel [156 ,157 ]
Abdelalim, A. A. [74 ]
Abdinov, O. [15 ]
Aben, R. [145 ,146 ]
Abi, B. [153 ]
Abolins, M. [125 ]
AbouZeid, O. S. [217 ]
Abramowicz, H. [211 ]
Abreu, H. [190 ]
Abulaiti, Y. [202 ,203 ]
Acharya, B. S. [224 ,225 ,245 ]
Adamczyk, L. [62 ]
Adams, D. L. [40 ]
Addy, T. N. [85 ]
Adelman, J. [242 ]
Adomeit, S. [136 ]
Adragna, P. [109 ]
Adye, T. [175 ]
Aefsky, S. [35 ]
Aguilar-Saavedra, J. A. [168 ,169 ,170 ]
Agustoni, M. [25 ,26 ]
Ahlen, S. P. [34 ]
Ahles, F. [73 ]
Ahmad, A. [205 ,206 ]
Ahsan, M. [65 ]
Aielli, G. [180 ,181 ]
Akesson, T. P. A. [115 ]
Akimoto, G. [213 ,214 ]
Akimov, A. V. [132 ]
Alam, M. A. [110 ]
Albert, J. [235 ]
Albrand, S. [82 ,83 ,84 ]
Aleksa, M. [46 ]
Aleksandrov, I. N. [95 ]
Alessandria, F. [126 ]
Alexa, C. [41 ]
Alexander, G. [211 ]
Alexandre, G. [74 ]
Alexopoulos, T. [14 ]
Alhroob, M. [224 ,226 ]
Aliev, M. [24 ]
Alimonti, G. [126 ]
Alison, J. [163 ]
Allbrooke, B. M. M. [27 ]
Allison, L. J. [103 ]
Allport, P. P. [106 ]
机构
[1] Univ Adelaide, Sch Chem & Phys, Adelaide, SA, Australia
[2] SUNY Albany, Dept Phys, Albany, NY 12222 USA
[3] Univ Alberta, Dept Phys, Edmonton, AB, Canada
[4] Ankara Univ, Dept Phys, TR-06100 Ankara, Turkey
[5] Gazi Univ, Dept Phys, Ankara, Turkey
[6] TOBB Univ Econ & Technol, Div Phys, Ankara, Turkey
[7] Turkish Atom Energy Commiss, Ankara, Turkey
[8] CNRS, IN2P3, LAPP, Annecy Le Vieux, France
[9] Univ Savoie, Annecy Le Vieux, France
[10] Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA
[11] Univ Arizona, Dept Phys, Tucson, AZ 85721 USA
[12] Univ Texas Arlington, Dept Phys, Arlington, TX 76019 USA
[13] Univ Athens, Dept Phys, Athens, Greece
[14] Natl Tech Univ Athens, Dept Phys, Zografos, Greece
[15] Azerbaijan Acad Sci, Inst Phys, Baku 370143, Azerbaijan
[16] Univ Autonoma Barcelona, Inst Fis Altes Energies, E-08193 Barcelona, Spain
[17] Univ Autonoma Barcelona, Dept Fis, E-08193 Barcelona, Spain
[18] ICREA, Barcelona, Spain
[19] Univ Belgrade, Inst Phys, Belgrade, Serbia
[20] Univ Belgrade, Vinca Inst Nucl Sci, Belgrade, Serbia
[21] Univ Bergen, Dept Phys & Technol, Bergen, Norway
[22] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Phys, Berkeley, CA 94720 USA
[23] Univ Calif Berkeley, Berkeley, CA 94720 USA
[24] Humboldt Univ, Dept Phys, Berlin, Germany
[25] Univ Bern, Albert Einstein Ctr Fundamental Phys, Bern, Switzerland
[26] Univ Bern, High Energy Phys Lab, Bern, Switzerland
[27] Univ Birmingham, Sch Phys & Astron, Birmingham, W Midlands, England
[28] Bogazici Univ, Dept Phys, Istanbul, Turkey
[29] Dogus Univ, Div Phys, Istanbul, Turkey
[30] Gaziantep Univ, Dept Engn Phys, Gaziantep, Turkey
[31] Ist Nazl Fis Nucl, Sez Bologna, Milan, Italy
[32] Univ Bologna, Dipartmento Fis, Bologna, Italy
[33] Univ Bonn, Inst Phys, Bonn, Germany
[34] Boston Univ, Dept Phys, Boston, MA 02215 USA
[35] Brandeis Univ, Dept Phys, Waltham, MA 02254 USA
[36] Univ Fed Rio de Janeiro, COPPE, EE, IF, Rio De Janeiro, Brazil
[37] Fed Univ Juiz de Fora UFJF, Juiz De Fora, Brazil
[38] Fed Univ Sao Joao del Rei UFSH, Sao Joao Del Rei, Brazil
[39] Univ Sao Paulo, Inst Fis, BR-01498 Sao Paulo, Brazil
[40] Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA
[41] Natl Inst Phys & Nucl Engn, Bucharest, Romania
[42] Univ Politehn Bucuresti, Bucharest, Romania
[43] Univ Buenos Aires, Dept Fis, Buenos Aires, DF, Argentina
[44] Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England
[45] Carleton Univ, Dept Phys, Ottawa, ON K1S 5B6, Canada
[46] CERN, Geneva, Switzerland
[47] Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA
[48] Pontificia Univ Catolica Chile, Dept Fis, Santiago, Chile
[49] Univ Tecn Federico Santa Maria, Dept Fis, Valparaiso, Chile
[50] Chinese Acad Sci, Inst High Energy Phys, Beijing, Peoples R China
来源
PHYSICAL REVIEW D | 2013年 / 88卷 / 01期
基金
加拿大自然科学与工程研究理事会; 美国国家科学基金会; 巴西圣保罗研究基金会;
关键词
PARTON DISTRIBUTIONS; PAIR PRODUCTION; ALGORITHMS; LHC;
D O I
10.1103/PhysRevD.88.012004
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
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.
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页数:28
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