Search for resonances decaying into top-quark pairs using fully hadronic decays in pp collisions with ATLAS at \( \sqrt{s}=7 \) TeV

Abstract

A search for resonances produced in 7 TeV proton-proton collisions and decaying into top-quark pairs is described. In this Letter events where the top-quark decay produces two massive jets with large transverse momenta recorded with the ATLAS detector at the Large Hadron Collider are considered. Two techniques that rely on jet substructure are used to separate top-quark jets from those arising from light quarks and gluons. In addition, each massive jet is required to have evidence of an associated bottom-quark decay. The data are consistent with the Standard Model, and limits can be set on the production cross section times branching fraction of a Z′ boson and a Kaluza-Klein gluon resonance. These limits exclude, at the 95% credibility level, Z′ bosons with masses 0.70-1.00 TeV as well as 1.28-1.32 TeV and Kaluza-Klein gluons with masses 0.70-1.62 TeV.

References

  1. [1]

    CDF collaboration, Limits on the production of narrow \( t\overline{t} \) resonances in \( p\overline{p} \) collisions at \( \sqrt{s}=1.96 \) TeV, Phys. Rev. D 77 (2008) 051102 [arXiv:0710.5335] [INSPIRE].

    Google Scholar 

  2. [2]

    CDF collaboration, Search for resonant \( t\overline{t} \) production in \( p\overline{p} \) collisions at \( \sqrt{s}=1.96 \) TeV, Phys. Rev. Lett. 100 (2008) 231801 [arXiv:0709.0705] [INSPIRE].

    Article  Google Scholar 

  3. [3]

    D0 collaboration, Search for \( t\overline{t} \) resonances in the lepton plus jets final state in \( p\overline{p} \) collisions at \( \sqrt{s}=1.96 \) TeV, Phys. Lett. B 668 (2008) 98 [arXiv:0804.3664] [INSPIRE].

    ADS  Google Scholar 

  4. [4]

    CDF collaboration, Search for new color-octet vector particle decaying to \( t\overline{t} \) in \( p\overline{p} \) collisions at \( \sqrt{s}=1.96 \) TeV, Phys. Lett. B 691 (2010) 183 [arXiv:0911.3112] [INSPIRE].

    ADS  Google Scholar 

  5. [5]

    CDF collaboration, A search for resonant production of \( t\overline{t} \) pairs in 4.8 fb −1 of integrated luminosity of \( p\overline{p} \) collisions at \( \sqrt{s}=1.96 \) TeV, Phys. Rev. D 84 (2011) 072004 [arXiv:1107.5063] [INSPIRE].

    Google Scholar 

  6. [6]

    D0 collaboration, Search for a narrow \( t\overline{t} \) resonance in \( p\overline{p} \) collisions at \( \sqrt{s}=1.96 \) TeV, Phys. Rev. D 85 (2012) 051101 [arXiv:1111.1271] [INSPIRE].

    Google Scholar 

  7. [7]

    ATLAS collaboration, A search for \( t\overline{t} \) resonances with the ATLAS detector in 2.05 fb −1 of proton-proton collisions at \( \sqrt{s}=7 \) TeV, Eur. Phys. J. C 72 (2012) 2083 [arXiv:1205.5371] [INSPIRE].

    ADS  Google Scholar 

  8. [8]

    ATLAS collaboration, A search for \( t\overline{t} \) resonances in lepton+jets events with highly boosted top quarks collected in pp collisions at \( \sqrt{s}=7 \) TeV with the ATLAS detector, JHEP 09 (2012) 041 [arXiv:1207.2409] [INSPIRE].

    ADS  Google Scholar 

  9. [9]

    CMS collaboration, Search for anomalous \( t\overline{t} \) production in the highly-boosted all-hadronic final state, JHEP 09 (2012) 029 [arXiv:1204.2488] [INSPIRE].

    ADS  Google Scholar 

  10. [10]

    T. Plehn, G.P. Salam and M. Spannowsky, Fat jets for a light Higgs, Phys. Rev. Lett. 104 (2010)111801 [arXiv:0910.5472] [INSPIRE].

    ADS  Article  Google Scholar 

  11. [11]

    T. Plehn, M. Spannowsky, M. Takeuchi and D. Zerwas, Stop reconstruction with tagged tops, JHEP 10 (2010) 078 [arXiv:1006.2833] [INSPIRE].

    ADS  Article  Google Scholar 

  12. [12]

    Y.L. Dokshitzer, G. Leder, S. Moretti and B. Webber, Better jet clustering algorithms, JHEP 08 (1997) 001 [hep-ph/9707323] [INSPIRE].

    ADS  Article  Google Scholar 

  13. [13]

    L.G. Almeida, S.J. Lee, G. Perez, G. Sterman and I. Sung, Template overlap method for massive jets, Phys. Rev. D 82 (2010) 054034 [arXiv:1006.2035] [INSPIRE].

    ADS  Google Scholar 

  14. [14]

    L.G. Almeida, O. Erdogan, J. Juknevich, S.J. Lee, G. Perez, et al., Three-particle templates for a boosted Higgs boson, Phys. Rev. D 85 (2012) 114046 [arXiv:1112.1957] [INSPIRE].

    ADS  Google Scholar 

  15. [15]

    M. Cacciari, G.P. Salam and G. Soyez, The \( {{\overline{k}}_t} \) jet clustering algorithm, JHEP 4 (2008) 63 [arXiv:0802.1189].

    ADS  Article  Google Scholar 

  16. [16]

    R.M. Harris, C.T. Hill and S.J. Parke, Cross section for topcolor Zdecaying to top-antitop, hep-ph/9911288.

  17. [17]

    K. Agashe, A. Belyaev, T. Krupovnickas, G. Perez and J. Virzi, LHC signals from warped extra dimensions, Phys. Rev. D 77 (2008) 015003 [hep-ph/0612015] [INSPIRE].

    ADS  Google Scholar 

  18. [18]

    B. Lillie, L. Randall and L.-T. Wang, The bulk RS KK-gluon at the LHC, JHEP 09 (2007) 074 [hep-ph/0701166] [INSPIRE].

    ADS  Article  Google Scholar 

  19. [19]

    B. Lillie, J. Shu and T.M. Tait, Kaluza-Klein gluons as a diagnostic of warped models, Phys. Rev. D 76 (2007) 115016 [arXiv:0706.3960] [INSPIRE].

    ADS  Google Scholar 

  20. [20]

    T. Sjöstrand, S. Mrenna and P.Z. Skands, A brief introduction to PYTHIA 8.1, Comput. Phys. Commun. 178 (2008) 852 [arXiv:0710.3820] [INSPIRE].

  21. [21]

    J. Alwall, P. Demin, S. de Visscher, R. Frederix, M. Herquet, F. Maltoni, T. Plehn, D.L. Rainwater and T. Stelzer, MadGraph/MadEvent v4: the new web generation, JHEP 9 (2007) 28 [arXiv:0706.2334].

    ADS  Article  Google Scholar 

  22. [22]

    J. Gao, C.S. Li, B.H. Li, H.X. Zhu and C.-P. Yuan, Next-to-leading order QCD corrections to a heavy resonance production and decay into top quark pair at the LHC, Phys. Rev. D 82 (2010) 014020 [arXiv:1004.0876].

    ADS  Google Scholar 

  23. [23]

    CMS collaboration, Search for resonant \( t\overline{t} \) production in lepton+jets events in pp collisions at \( \sqrt{s}=7 \) TeV, JHEP 12 (2012) 015 [arXiv:1209.4397] [INSPIRE].

    ADS  Google Scholar 

  24. [24]

    ATLAS collaboration, The ATLAS experiment at the CERN large hadron collider, 2008 JINST 3 S08003 [INSPIRE].

  25. [25]

    L. Evans and P. Bryant, The LHC machine, 2008 JINST 3 S08001 [INSPIRE].

  26. [26]

    ATLAS collaboration, Improved luminosity determination in pp collisions at \( \sqrt{s}=7 \) TeV using the ATLAS detector at the LHC, ATLAS-CONF-2012-080 (2012).

  27. [27]

    ATLAS collaboration, Luminosity determination in pp collisions at \( \sqrt{s}=7 \) TeV using the ATLAS detector at the LHC, Eur. Phys. J. C 71 (2011) 1630 [arXiv:1101.2185] [INSPIRE].

    ADS  Google Scholar 

  28. [28]

    S. Frixione and B.R. Webber, Matching NLO QCD computations and parton shower simulations, JHEP 06 (2002) 029 [hep-ph/0204244] [INSPIRE].

    ADS  Article  Google Scholar 

  29. [29]

    S. Frixione, P. Nason and B.R. Webber, Matching NLO QCD and parton showers in heavy flavor production, JHEP 08 (2003) 007 [hep-ph/0305252] [INSPIRE].

    ADS  Article  Google Scholar 

  30. [30]

    H.-L. Lai, M. Guzzi, J. Huston, Z. Li, P.M. Nadolsky, et al., New parton distributions for collider physics, Phys. Rev. D 82 (2010) 074024 [arXiv:1007.2241] [INSPIRE].

    ADS  Google Scholar 

  31. [31]

    G. Corcella, I. Knowles, G. Marchesini, S. Moretti, K. Odagiri, et al., HERWIG 6.5 release note, hep-ph/0210213 [INSPIRE].

  32. [32]

    J.M. Butterworth, J.R. Forshaw and M.H. Seymour, Multiparton interactions in photoproduction at HERA, Zeit. Phys. C 72 (1996) 637 [hep-ph/9601371].

    ADS  Google Scholar 

  33. [33]

    M. Aliev, H. Lacker, U. Langenfeld, S. Moch, P. Uwer and M. Wiedermann, HATHORHadronic top and heavy quarks cross section calculatoR, Comp. Phys. Comm. 182 (2011) 1034 [arXiv:1007.1327].

    ADS  MATH  Article  Google Scholar 

  34. [34]

    A. Martin, W. Stirling, R. Thorne and G. Watt, Parton distributions for the LHC, Eur. Phys. J. C 63 (2009) 189 [arXiv:0901.0002] [INSPIRE].

    ADS  Article  Google Scholar 

  35. [35]

    T. Sjöstrand, S. Mrenna and P.Z. Skands, PYTHIA 6.4 physics and manual, JHEP 05 (2006) 026 [hep-ph/0603175] [INSPIRE].

    ADS  Article  Google Scholar 

  36. [36]

    J. Pumplin, D. Stump, J. Huston, H. Lai, P.M. Nadolsky, et al., New generation of parton distributions with uncertainties from global QCD analysis, JHEP 07 (2002) 012 [hep-ph/0201195] [INSPIRE].

    ADS  Article  Google Scholar 

  37. [37]

    ATLAS collaboration, The ATLAS simulation infrastructure, Eur. Phys. J. C 70 (2010) 823 [arXiv:1005.4568] [INSPIRE].

    ADS  Google Scholar 

  38. [38]

    GEANT4 collaboration, S. Agostinelli et al., GEANT4: a simulation toolkit, Nucl. Instrum. Meth. A 506 (2003) 250 [INSPIRE].

    ADS  Google Scholar 

  39. [39]

    W. Lampl et al., Calorimeter clustering algorithms: description and performance, ATL-LARG-PUB-2008-002 (2008).

  40. [40]

    ATLAS collaboration, Jet energy measurement with the ATLAS detector in proton-proton collisions at \( \sqrt{s}=7 \) TeV, arXiv:1112.6426 [INSPIRE].

  41. [41]

    M. Cacciari, G.P. Salam and G. Soyez, The \( {{\overline{k}}_t} \) jet clustering algorithm, JHEP 04 (2008) 063 [arXiv:0802.1189] [INSPIRE].

    ADS  Article  Google Scholar 

  42. [42]

    M. Cacciari, G.P. Salam and G. Soyez, FastJet user manual, Eur. Phys. J. C 72 (2012) 1896 [arXiv:1111.6097] [INSPIRE].

    ADS  Article  Google Scholar 

  43. [43]

    ATLAS collaboration, Properties of jets and inputs to jet reconstruction and calibration with the atlas detector using proton-proton collisions at \( \sqrt{s}=7 \) TeV, ATLAS-CONF-2010-053 (2010).

  44. [44]

    ATLAS collaboration, Measurement of the b-tag efficiency in a sample of jets containing muons with 5 fb −1 of data from the ATLAS detector, ATLAS-CONF-2012-043 (2012).

  45. [45]

    ATLAS collaboration, A search for \( t\overline{t} \) resonances in the lepton plus jets final state using 4.66 fb −1 of pp collisions at \( \sqrt{s}=7 \) TeV, ATLAS-CONF-2012-136 (2012).

  46. [46]

    ATLAS collaboration, Performance of large-R jets and jet substructure reconstruction with the ATLAS detector, ATLAS-CONF-2012-065 (2012).

  47. [47]

    J.M. Butterworth, A.R. Davison, M. Rubin and G.P. Salam, Jet substructure as a new Higgs search channel at the LHC, Phys. Rev. Lett. 100 (2008) 242001 [arXiv:0802.2470] [INSPIRE].

    ADS  Article  Google Scholar 

  48. [48]

    G.P. Salam and G. Soyez, A practical seedless infrared-safe cone jet algorithm, JHEP 05 (2007) 086 [arXiv:0704.0292] [INSPIRE].

    ADS  Article  Google Scholar 

  49. [49]

    S. Catani, Y.L. Dokshitzer, M. Seymour and B. Webber, Longitudinally invariant K t clustering algorithms for hadron hadron collisions, Nucl. Phys. B 406 (1993) 187 [INSPIRE].

    ADS  Article  Google Scholar 

  50. [50]

    Tevatron Electroweak Working Group, CDF, D0 collaborations, Combination of CDF and D0 results on the mass of the top quark using up to 5.8 fb −1 of data, arXiv:1107.5255 [INSPIRE].

  51. [51]

    G.C. Blazey, J.R. Dittmann, S.D. Ellis, V.D. Elvira, K. Frame, et al., Run II jet physics, hep-ex/0005012 [INSPIRE].

  52. [52]

    ATLAS collaboration, Jet mass and substructure of inclusive jets in \( \sqrt{s}=7 \) TeV pp collisions with the ATLAS experiment, JHEP 5 (2012) 128 [arXiv:1203.4606].

    ADS  Google Scholar 

  53. [53]

    ATLAS collaboration, ATLAS measurements of the properties of jets for boosted particle searches, Phys. Rev. D 86 (2012) 072006 [arXiv:1206.5369] [INSPIRE].

    ADS  Google Scholar 

  54. [54]

    R. Alon, E. Duchovni, G. Perez, A.P. Pranko and P.K. Sinervo, Data-driven method of pile-up correction for the substructure of massive jets, Phys. Rev. D 84 (2011) 114025 [arXiv:1101.3002].

    ADS  Google Scholar 

  55. [55]

    CDF collaboration, Study of substructure of high transverse momentum jets produced in proton-antiproton collisions at \( \sqrt{s}=1.96 \) TeV, Phys. Rev. D 85 (2012) 091101 [arXiv:1106.5952] [INSPIRE].

    Google Scholar 

  56. [56]

    K. Blum, C. Delaunay, O. Gedalia, Y. Hochberg, S.J. Lee, et al., Implications of the CDF \( t\overline{t} \) forward-backward asymmetry for boosted top physics, Phys. Lett. B 702 (2011) 364 [arXiv:1102.3133] [INSPIRE].

    ADS  Google Scholar 

  57. [57]

    ATLAS collaboration, Measurement of the mistag rate with 5 fb −1 of data collected by the ATLAS detector, ATLAS-CONF-2012-040 (2012).

  58. [58]

    ATLAS collaboration, Measuring the b-tag efficiency in a top-pair sample with 4.7 fb −1 of data from the ATLAS detector, ATLAS-CONF-2012-097 (2012).

  59. [59]

    A. Martin, W. Stirling, R. Thorne and G. Watt, Uncertainties on αs in global PDF analyses and implications for predicted hadronic cross sections, Eur. Phys. J. C 64 (2009) 653 [arXiv:0905.3531] [INSPIRE].

    ADS  Article  Google Scholar 

  60. [60]

    NNPDF collaboration, R.D. Ball et al., Unbiased global determination of parton distributions and their uncertainties at NNLO and at LO, Nucl. Phys. B 855 (2012) 153 [arXiv:1107.2652] [INSPIRE].

    ADS  Article  Google Scholar 

  61. [61]

    M. Botje, J. Butterworth, A. Cooper-Sarkar, A. de Roeck, J. Feltesse, et al., The PDF4LHC working group interim recommendations, arXiv:1101.0538 [INSPIRE].

  62. [62]

    B.P. Kersevan and E. Richter-Was, The Monte Carlo event generator AcerMC version 2.0 with interfaces to PYTHIA 6.2 and HERWIG 6.5, hep-ph/0405247 [INSPIRE].

  63. [63]

    ATLAS collaboration, Measurement of \( t\overline{t} \) production with a veto on additional central jet activity in pp collisions at \( \sqrt{s}=7 \) TeV using the ATLAS detector, Eur. Phys. J. C 72 (2012) 2043 [arXiv:1203.5015] [INSPIRE].

    ADS  Google Scholar 

  64. [64]

    S. Frixione, P. Nason and C. Oleari, Matching NLO QCD computations with parton shower simulations: the POWHEG method, JHEP 11 (2007) 070 [arXiv:0709.2092] [INSPIRE].

    ADS  Article  Google Scholar 

  65. [65]

    A.V. Manohar and M. Trott, Electroweak Sudakov corrections and the top quark forward-backward asymmetry, Phys. Lett. B 711 (2012) 313 [arXiv:1201.3926] [INSPIRE].

    ADS  Google Scholar 

  66. [66]

    D0 collaboration, A recipe for the construction of confidence limits, FERMILAB-TM-2104 (2000).

  67. [67]

    K. Joshi, A.D. Pilkington and M. Spannowsky, The dependency of boosted tagging algorithms on the event colour structure, Phys. Rev. D 86 (2012) 114016 [arXiv:1207.6066] [INSPIRE].

    ADS  Google Scholar 

Download references

Author information

Affiliations

Authors

Consortia

Additional information

Deceased (V.V. Ammosov, E. Arik, A. Bogouch, H.M. Braun, C. Caso, L. Chikovani, Y. Doi, B.A. Dolgoshein, G.M. Kolachev, M.J. Losty, K.W. McFarlane, S.V. Mouraviev, F. Pastore, G. Sauvage, A.N. Sisakyan, P. Stavina, J.A. Strong, I. Stumer, M. Virchaux, V.V. Zmouchko)

Rights and permissions

This article is published under an open access license. Please check the 'Copyright Information' section either on this page or in the PDF for details of this license and what re-use is permitted. If your intended use exceeds what is permitted by the license or if you are unable to locate the licence and re-use information, please contact the Rights and Permissions team.

About this article

Cite this article

The ATLAS collaboration., Aad, G., Abajyan, T. et al. Search for resonances decaying into top-quark pairs using fully hadronic decays in pp collisions with ATLAS at \( \sqrt{s}=7 \) TeV. J. High Energ. Phys. 2013, 116 (2013). https://doi.org/10.1007/JHEP01(2013)116

Download citation

Keywords

  • Hadron-Hadron Scattering