Search for tt̄ resonances in the lepton plus jets final state with ATLAS using 4.7 fb–1of pp collisions at √s = 7 TeV

ATLAS Collaboration

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Abstract

A search for new particles that decay into top quark pairs (tt) is performed with the ATLAS experiment at the LHC using an integrated luminosity of 4.7 fb–1of proton–proton (pp) collision data collected at a center-of-mass energy √s = 7 TeV. In the tt̄→ WbWb decay, the lepton plus jets final state is used, where one W boson decays leptonically and the other hadronically. The tt̄system 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 tt̄invariant mass spectrum is performed. No evidence for a tt̄resonance 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 Γ/m = 15.3%. A Kaluza–Klein excitation of the gluon in a Randall–Sundrum model is excluded for masses below 2.07 TeV.

Original languageEnglish
Article number012004
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volume88
Issue number1
DOIs
Publication statusPublished - Jan 1 2013

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leptons
collisions
bosons
particle decay
radii
octets
decay
substructures
mass spectra
center of mass
luminosity
quarks
color
cross sections
excitation
energy

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Physics and Astronomy (miscellaneous)

Cite this

@article{a14c6af228034449aa44c8fcf20768e3,
title = "Search for tt̄ resonances in the lepton plus jets final state with ATLAS using 4.7 fb–1of pp collisions at √s = 7 TeV",
abstract = "A search for new particles that decay into top quark pairs (tt) is performed with the ATLAS experiment at the LHC using an integrated luminosity of 4.7 fb–1of proton–proton (pp) collision data collected at a center-of-mass energy √s = 7 TeV. In the tt̄→ WbWb decay, the lepton plus jets final state is used, where one W boson decays leptonically and the other hadronically. The tt̄system 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 tt̄invariant mass spectrum is performed. No evidence for a tt̄resonance 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 Γ/m = 15.3{\%}. A Kaluza–Klein excitation of the gluon in a Randall–Sundrum model is excluded for masses below 2.07 TeV.",
author = "{ATLAS Collaboration} and G. Aad and T. Abajyan and B. Abbott and J. Abdallah and {Abdel Khalek}, S. and Abdelalim, {A. A.} and O. Abdinov and R. Aben and B. Abi and M. Abolins and Abouzeid, {O. S.} and H. Abramowicz and H. Abreu and Acharya, {B. S.} and L. Adamczyk and Adams, {D. L.} and Addy, {T. N.} and J. Adelman and S. Adomeit and P. Adragna and T. Adye and S. Aefsky and Aguilar-Saavedra, {J. A.} and M. Agustoni and M. Aharrouche and Ahlen, {S. P.} and F. Ahles and A. Ahmad and M. Ahsan and G. Aielli and T. Akdogan and {\AA}kesson, {T. P.A.} and G. Akimoto and Akimov, {A. V.} and Alam, {M. S.} and Alam, {M. A.} and J. Albert and S. Albrand and M. Aleksa and Aleksandrov, {I. N.} and F. Alessandria and C. Alexa and G. Alexander and G. Alexandre and T. Alexopoulos and M. Alhroob and M. Aliev and G. Alimonti and J. Alison and Allbrooke, {B. M.M.}",
year = "2013",
month = "1",
day = "1",
doi = "10.1103/PhysRevD.88.012004",
language = "English",
volume = "88",
journal = "Physical Review D - Particles, Fields, Gravitation and Cosmology",
issn = "1550-7998",
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TY - JOUR

T1 - Search for tt̄ resonances in the lepton plus jets final state with ATLAS using 4.7 fb–1of pp collisions at √s = 7 TeV

AU - ATLAS Collaboration

AU - Aad, G.

AU - Abajyan, T.

AU - Abbott, B.

AU - Abdallah, J.

AU - Abdel Khalek, S.

AU - Abdelalim, A. A.

AU - Abdinov, O.

AU - Aben, R.

AU - Abi, B.

AU - Abolins, M.

AU - Abouzeid, O. S.

AU - Abramowicz, H.

AU - Abreu, H.

AU - Acharya, B. S.

AU - Adamczyk, L.

AU - Adams, D. L.

AU - Addy, T. N.

AU - Adelman, J.

AU - Adomeit, S.

AU - Adragna, P.

AU - Adye, T.

AU - Aefsky, S.

AU - Aguilar-Saavedra, J. A.

AU - Agustoni, M.

AU - Aharrouche, M.

AU - Ahlen, S. P.

AU - Ahles, F.

AU - Ahmad, A.

AU - Ahsan, M.

AU - Aielli, G.

AU - Akdogan, T.

AU - Åkesson, T. P.A.

AU - Akimoto, G.

AU - Akimov, A. V.

AU - Alam, M. S.

AU - Alam, M. A.

AU - Albert, J.

AU - Albrand, S.

AU - Aleksa, M.

AU - Aleksandrov, I. N.

AU - Alessandria, F.

AU - Alexa, C.

AU - Alexander, G.

AU - Alexandre, G.

AU - Alexopoulos, T.

AU - Alhroob, M.

AU - Aliev, M.

AU - Alimonti, G.

AU - Alison, J.

AU - Allbrooke, B. M.M.

PY - 2013/1/1

Y1 - 2013/1/1

N2 - A search for new particles that decay into top quark pairs (tt) is performed with the ATLAS experiment at the LHC using an integrated luminosity of 4.7 fb–1of proton–proton (pp) collision data collected at a center-of-mass energy √s = 7 TeV. In the tt̄→ WbWb decay, the lepton plus jets final state is used, where one W boson decays leptonically and the other hadronically. The tt̄system 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 tt̄invariant mass spectrum is performed. No evidence for a tt̄resonance 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 Γ/m = 15.3%. A Kaluza–Klein excitation of the gluon in a Randall–Sundrum model is excluded for masses below 2.07 TeV.

AB - A search for new particles that decay into top quark pairs (tt) is performed with the ATLAS experiment at the LHC using an integrated luminosity of 4.7 fb–1of proton–proton (pp) collision data collected at a center-of-mass energy √s = 7 TeV. In the tt̄→ WbWb decay, the lepton plus jets final state is used, where one W boson decays leptonically and the other hadronically. The tt̄system 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 tt̄invariant mass spectrum is performed. No evidence for a tt̄resonance 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 Γ/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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U2 - 10.1103/PhysRevD.88.012004

DO - 10.1103/PhysRevD.88.012004

M3 - Article

AN - SCOPUS:84881363612

VL - 88

JO - Physical Review D - Particles, Fields, Gravitation and Cosmology

JF - Physical Review D - Particles, Fields, Gravitation and Cosmology

SN - 1550-7998

IS - 1

M1 - 012004

ER -