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Uncovering quasi-degenerate Kaluza-Klein electro-weak gauge bosons with top asymmetries at the LHC

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Abstract

By exploiting the correlation between charge and spin polarisation asymmetries in \( t\overline{t} \), we show that combining the two observables could identify the presence of quasi-degenerate states in a resonant signal at the LHC. As an example, we investigate experimental signatures emerging in top-antitop final states in the context of a model where the Standard Model Electro-Weak sector is allowed to propagate in large extra-dimensions of TeV−1 size while the colour sector is localised. Assuming current experimantal constraints from the 7 and 8 TeV runs and taking into account the estimated top (anti-top) reconstruction efficiencies, we find that the 14 TeV upgraded LHC with the planned integrated luminosity L = 100 fb−1 could access these quasi-degenerate multiple resonances and explore for the first time the rich phenomenology in the asymmetry observables. The main outcome would be having measurable quantities, complementary to the usual total and differential cross sections, capable of distiguishing a quasi-degenerate multiply resonant spectrum from a ‘standard’ single resonance that could present a similar signal in a bump hunt analysis.

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References

  1. I. Antoniadis, A possible new dimension at a few TeV, Phys. Lett. B 246 (1990) 377 [INSPIRE].

    MathSciNet  ADS  Google Scholar 

  2. N. Arkani-Hamed, S. Dimopoulos and G. Dvali, The hierarchy problem and new dimensions at a millimeter, Phys. Lett. B 429 (1998) 263 [hep-ph/9803315] [INSPIRE].

    ADS  Google Scholar 

  3. I. Antoniadis, N. Arkani-Hamed, S. Dimopoulos and G. Dvali, New dimensions at a millimeter to a Fermi and superstrings at a TeV, Phys. Lett. B 436 (1998) 257 [hep-ph/9804398] [INSPIRE].

    ADS  Google Scholar 

  4. I. Antoniadis and C. Bachas, Branes and the gauge hierarchy, Phys. Lett. B 450 (1999) 83 [hep-th/9812093] [INSPIRE].

    MathSciNet  ADS  Google Scholar 

  5. J.D. Lykken, Weak scale superstrings, Phys. Rev. D 54 (1996) 3693 [hep-th/9603133] [INSPIRE].

    MathSciNet  ADS  Google Scholar 

  6. I. Antoniadis and B. Pioline, Low scale closed strings and their duals, Nucl. Phys. B 550 (1999) 41 [hep-th/9902055] [INSPIRE].

    MathSciNet  ADS  Google Scholar 

  7. K. Benakli and Y. Oz, Small instantons and weak scale string theory, Phys. Lett. B 472 (2000) 83 [hep-th/9910090] [INSPIRE].

    MathSciNet  ADS  Google Scholar 

  8. K. Benakli, Phenomenology of low quantum gravity scale models, Phys. Rev. D 60 (1999) 104002 [hep-ph/9809582] [INSPIRE].

    MathSciNet  ADS  Google Scholar 

  9. C. Burgess, L.E. Ibáñez and F. Quevedo, Strings at the intermediate scale, or is the Fermi scale dual to the Planck scale?, Phys. Lett. B 447 (1999) 257 [hep-ph/9810535] [INSPIRE].

    ADS  Google Scholar 

  10. G. Shiu and S.H. Tye, TeV scale superstring and extra dimensions, Phys. Rev. D 58 (1998) 106007 [hep-th/9805157] [INSPIRE].

    MathSciNet  ADS  Google Scholar 

  11. Z. Kakushadze and S.H. Tye, Brane world, Nucl. Phys. B 548 (1999) 180 [hep-th/9809147] [INSPIRE].

    Article  MathSciNet  ADS  Google Scholar 

  12. L.E. Ibáñez, C. Muñoz and S. Rigolin, Aspect of type-I string phenomenology, Nucl. Phys. B 553 (1999) 43 [hep-ph/9812397] [INSPIRE].

    Article  ADS  Google Scholar 

  13. G. Aldazabal, L.E. Ibáñez and F. Quevedo, Standard-like models with broken supersymmetry from type-I string vacua, JHEP 01 (2000) 031 [hep-th/9909172] [INSPIRE].

    Article  ADS  Google Scholar 

  14. I. Antoniadis and K. Benakli, Limits on extra dimensions in orbifold compactifications of superstrings, Phys. Lett. B 326 (1994) 69 [hep-th/9310151] [INSPIRE].

    ADS  Google Scholar 

  15. I. Antoniadis, C. Muñoz and M. Quirós, Dynamical supersymmetry breaking with a large internal dimension, Nucl. Phys. B 397 (1993) 515 [hep-ph/9211309] [INSPIRE].

    Article  ADS  Google Scholar 

  16. I. Antoniadis, K. Benakli and M. Quirós, Production of Kaluza-Klein states at future colliders, Phys. Lett. B 331 (1994) 313 [hep-ph/9403290] [INSPIRE].

    ADS  Google Scholar 

  17. K. Benakli, Perturbative supersymmetry breaking in orbifolds with Wilson line backgrounds, Phys. Lett. B 386 (1996) 106 [hep-th/9509115] [INSPIRE].

    MathSciNet  ADS  Google Scholar 

  18. I. Antoniadis and M. Quirós, Large radii and string unification, Phys. Lett. B 392 (1997) 61 [hep-th/9609209] [INSPIRE].

    ADS  Google Scholar 

  19. I. Antoniadis, S. Dimopoulos and G. Dvali, Millimeter range forces in superstring theories with weak scale compactification, Nucl. Phys. B 516 (1998) 70 [hep-ph/9710204] [INSPIRE].

    Article  MathSciNet  ADS  Google Scholar 

  20. A. Pomarol and M. Quirós, The standard model from extra dimensions, Phys. Lett. B 438 (1998) 225 [hep-ph/9806263] [INSPIRE].

    ADS  Google Scholar 

  21. I. Antoniadis, S. Dimopoulos, A. Pomarol and M. Quirós, Soft masses in theories with supersymmetry breaking by TeV compactification, Nucl. Phys. B 544 (1999) 503 [hep-ph/9810410] [INSPIRE].

    Article  ADS  Google Scholar 

  22. A. Delgado, A. Pomarol and M. Quirós, Supersymmetry and electroweak breaking from extra dimensions at the TeV scale, Phys. Rev. D 60 (1999) 095008 [hep-ph/9812489] [INSPIRE].

    ADS  Google Scholar 

  23. P. Nath and M. Yamaguchi, Effects of extra space-time dimensions on the Fermi constant, Phys. Rev. D 60 (1999) 116004 [hep-ph/9902323] [INSPIRE].

    ADS  Google Scholar 

  24. P. Nath and M. Yamaguchi, Effects of Kaluza-Klein excitations on (g μ  − 2), Phys. Rev. D 60 (1999) 116006 [hep-ph/9903298] [INSPIRE].

    ADS  Google Scholar 

  25. M. Masip and A. Pomarol, Effects of SM Kaluza-Klein excitations on electroweak observables, Phys. Rev. D 60 (1999) 096005 [hep-ph/9902467] [INSPIRE].

    ADS  Google Scholar 

  26. W.J. Marciano, Fermi constants andnew physics’, Phys. Rev. D 60 (1999) 093006 [hep-ph/9903451] [INSPIRE].

    ADS  Google Scholar 

  27. A. Strumia, Bounds on Kaluza-Klein excitations of the SM vector bosons from electroweak tests, Phys. Lett. B 466 (1999) 107 [hep-ph/9906266] [INSPIRE].

    ADS  Google Scholar 

  28. R. Casalbuoni, S. De Curtis, D. Dominici and R. Gatto, SM Kaluza-Klein excitations and electroweak precision tests, Phys. Lett. B 462 (1999) 48 [hep-ph/9907355] [INSPIRE].

    ADS  Google Scholar 

  29. C.D. Carone, Electroweak constraints on extended models with extra dimensions, Phys. Rev. D 61 (2000) 015008 [hep-ph/9907362] [INSPIRE].

    ADS  Google Scholar 

  30. A. Delgado, A. Pomarol and M. Quirós, Electroweak and flavor physics in extensions of the standard model with large extra dimensions, JHEP 01 (2000) 030 [hep-ph/9911252] [INSPIRE].

    Article  ADS  Google Scholar 

  31. I. Antoniadis, K. Benakli and M. Quirós, Direct collider signatures of large extra dimensions, Phys. Lett. B 460 (1999) 176 [hep-ph/9905311] [INSPIRE].

    ADS  Google Scholar 

  32. P. Nath, Y. Yamada and M. Yamaguchi, Probing the nature of compactification with Kaluza-Klein excitations at the Large Hadron Collider, Phys. Lett. B 466 (1999) 100 [hep-ph/9905415] [INSPIRE].

    ADS  Google Scholar 

  33. T.G. Rizzo and J.D. Wells, Electroweak precision measurements and collider probes of the standard model with large extra dimensions, Phys. Rev. D 61 (2000) 016007 [hep-ph/9906234] [INSPIRE].

    ADS  Google Scholar 

  34. L. Basso, K. Mimasu and S. Moretti, Z signals in polarised top-antitop final states, JHEP 09 (2012) 024 [arXiv:1203.2542] [INSPIRE].

    Article  ADS  Google Scholar 

  35. L. Basso, K. Mimasu and S. Moretti, Non-exotic Z signals in ℓ + , \( b\overline{b} \) and \( t\overline{t} \) final states at the LHC, JHEP 11 (2012) 060 [arXiv:1208.0019] [INSPIRE].

    Article  ADS  Google Scholar 

  36. L. Basso, K. Mimasu and S. Moretti, Distinguishing Z models with polarised top pairs, arXiv:1209.3622 [INSPIRE].

  37. L. Basso, K. Mimasu and S. Moretti, Z signals in polarised top-antitop final states at the LHC, arXiv:1211.5470 [INSPIRE].

  38. L. Basso, K. Mimasu and S. Moretti, The role of charge and spin asymmetries in profiling Z tt events, arXiv:1211.5599 [INSPIRE].

  39. D. Barducci, S. De Curtis, K. Mimasu and S. Moretti, Multiple Z \( t\overline{t} \) signals in a 4D composite Higgs model, arXiv:1212.5948 [INSPIRE].

  40. D. Krohn, T. Liu, J. Shelton and L.-T. Wang, A polarized view of the top asymmetry, Phys. Rev. D 84 (2011) 074034 [arXiv:1105.3743] [INSPIRE].

    ADS  Google Scholar 

  41. R.W. Brown, D. Sahdev and K.O. Mikaelian, Probing higher order QCD: charge conjugation asymmetries from two gluon exchange, Phys. Rev. Lett. 43 (1979) 1069 [INSPIRE].

    Article  ADS  Google Scholar 

  42. J.H. Kuhn and G. Rodrigo, Charge asymmetry of heavy quarks at hadron colliders, Phys. Rev. D 59 (1999) 054017 [hep-ph/9807420] [INSPIRE].

    ADS  Google Scholar 

  43. S. Moretti, M. Nolten and D. Ross, Weak corrections to gluon-induced top-antitop hadro-production, Phys. Lett. B 639 (2006) 513 [Erratum ibid. B 660 (2008) 607-609] [hep-ph/0603083] [INSPIRE].

  44. S. Moretti and D. Ross, On the top-antitop invariant mass spectrum at the LHC from a Higgs boson signal perspective, Phys. Lett. B 712 (2012) 245 [arXiv:1203.3746] [INSPIRE].

    ADS  Google Scholar 

  45. J.H. Kuhn, A. Scharf and P. Uwer, Electroweak corrections to top-quark pair production in quark-antiquark annihilation, Eur. Phys. J. C 45 (2006) 139 [hep-ph/0508092] [INSPIRE].

    Article  ADS  Google Scholar 

  46. J.H. Kuhn, A. Scharf and P. Uwer, Electroweak effects in top-quark pair production at hadron colliders, Eur. Phys. J. 51 (2007) 37 [hep-ph/0610335] [INSPIRE].

    Article  ADS  Google Scholar 

  47. W. Hollik and M. Kollar, NLO QED contributions to top-pair production at hadron collider, Phys. Rev. D 77 (2008) 014008 [arXiv:0708.1697] [INSPIRE].

    ADS  Google Scholar 

  48. W. Hollik, M. Kollar and M.K. Trenkel, EW NLO corrections to pair production of top-squarks at the LHC, arXiv:0710.2472 [INSPIRE].

  49. W. Bernreuther, M. Fucker and Z.G. Si, Mixed QCD and weak corrections to t anti-t production by quark-antiquark annihilation, Int. J. Mod .Phys. A 21 (2006) 914 [hep-ph/0509210] [INSPIRE].

    ADS  Google Scholar 

  50. W. Bernreuther, M. Fucker and Z.-G. Si, Weak interaction corrections to hadronic top quark pair production: contributions from quark-gluon and \( b\overline{b} \) induced reactions, Phys. Rev. D 78 (2008) 017503 [arXiv:0804.1237] [INSPIRE].

    ADS  Google Scholar 

  51. W. Bernreuther, M. Fucker and Z.-G. Si, Electroweak corrections to \( t\overline{t} \) production at hadron colliders, Nuovo Cim. B 123 (2008) 1036 [arXiv:0808.1142] [INSPIRE].

    ADS  Google Scholar 

  52. T. Stelzer and S. Willenbrock, Spin correlation in top quark production at hadron colliders, Phys. Lett. B 374 (1996) 169 [hep-ph/9512292] [INSPIRE].

    ADS  Google Scholar 

  53. G. Mahlon and S.J. Parke, Angular correlations in top quark pair production and decay at hadron colliders, Phys. Rev. D 53 (1996) 4886 [hep-ph/9512264] [INSPIRE].

    ADS  Google Scholar 

  54. G. Mahlon and S.J. Parke, Spin correlation effects in top quark pair production at the LHC, Phys. Rev. D 81 (2010) 074024 [arXiv:1001.3422] [INSPIRE].

    ADS  Google Scholar 

  55. W. Bernreuther, A. Brandenburg, Z. Si and P. Uwer, Top quark spin correlations at hadron colliders: Predictions at next-to-leading order QCD, Phys. Rev. Lett. 87 (2001) 242002 [hep-ph/0107086] [INSPIRE].

    Article  ADS  Google Scholar 

  56. W. Bernreuther, A. Brandenburg, Z. Si and P. Uwer, Investigation of top quark spin correlations at hadron collider, hep-ph/0410197 [INSPIRE].

  57. R.M. Godbole, K. Rao, S.D. Rindani and R.K. Singh, On measurement of top polarization as a probe of \( t\overline{t} \) production mechanisms at the LHC, JHEP 11 (2010) 144 [arXiv:1010.1458] [INSPIRE].

    Article  ADS  Google Scholar 

  58. CMS collaboration, Jet substructure algorithms, CMS-PAS-JME-10-013 (Jet Substructure Algorithms).

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

  60. ATLAS collaboration, Search for resonances decaying into top-quark pairs using fully hadronic decays in pp collisions with ATLAS at \( \sqrt{s}=7 \) TeV, JHEP 01 (2013) 116 [arXiv:1211.2202] [INSPIRE].

    ADS  Google Scholar 

  61. 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 

  62. 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 

  63. J. Shelton, Polarized tops from new physics: signals and observables, Phys. Rev. D 79 (2009) 014032 [arXiv:0811.0569] [INSPIRE].

    ADS  Google Scholar 

  64. D. Krohn, J. Shelton and L.-T. Wang, Measuring the polarization of boosted hadronic tops, JHEP 07 (2010) 041 [arXiv:0909.3855] [INSPIRE].

    Article  ADS  Google Scholar 

  65. A. Papaefstathiou and K. Sakurai, Determining the helicity structure of third generation resonances, JHEP 06 (2012) 069 [arXiv:1112.3956] [INSPIRE].

    Article  ADS  Google Scholar 

  66. T. Appelquist, H.-C. Cheng and B.A. Dobrescu, Bounds on universal extra dimensions, Phys. Rev. D 64 (2001) 035002 [hep-ph/0012100] [INSPIRE].

    ADS  Google Scholar 

  67. E. Accomando, I. Antoniadis and K. Benakli, Looking for TeV scale strings and extra dimensions, Nucl. Phys. B 579 (2000) 3 [hep-ph/9912287] [INSPIRE].

    Article  ADS  Google Scholar 

  68. H.-C. Cheng, K.T. Matchev and M. Schmaltz, Radiative corrections to Kaluza-Klein masses, Phys. Rev. D 66 (2002) 036005 [hep-ph/0204342] [INSPIRE].

    ADS  Google Scholar 

  69. G. Cacciapaglia, A. Deandrea and S. De Curtis, Nearby resonances beyond the Breit-Wigner approximation, Phys. Lett. B 682 (2009) 43 [arXiv:0906.3417] [INSPIRE].

    ADS  Google Scholar 

  70. CMS collaboration, Search for narrow resonances using the dijet mass spectrum in pp collisions at \( \sqrt{s} \) of 8 TeV, CMS-PAS-EXO-12-016 (2012).

  71. CMS collaboration, Search for narrow resonances using the dijet mass spectrum with 19.6 fb −1 of pp collisions at \( \sqrt{s}=8 \) TeV, CMS-PAS-EXO-12-059 (2012).

  72. CMS collaboration, Search for high-mass resonances decaying to top quark pairs in the lepton+jets channel, CMS-PAS-EXO-11-093 (2011).

  73. C.T. Hill, Topcolor: top quark condensation in a gauge extension of the standard model, Phys. Lett. B 266 (1991) 419 [INSPIRE].

    ADS  Google Scholar 

  74. C.T. Hill, Topcolor assisted technicolor, Phys. Lett. B 345 (1995) 483 [hep-ph/9411426] [INSPIRE].

    ADS  Google Scholar 

  75. H. Murayama, I. Watanabe and K. Hagiwara, HELAS: HELicity amplitude subroutines for Feynman diagram evaluations, KEK Report 91-11 (1992).

  76. T. Stelzer and W. Long, Automatic generation of tree level helicity amplitudes, Comput. Phys. Commun. 81 (1994) 357 [hep-ph/9401258] [INSPIRE].

    Article  ADS  Google Scholar 

  77. J. Pumplin et al., New generation of parton distributions with uncertainties from global QCD analysis, JHEP 07 (2002) 012 [hep-ph/0201195] [INSPIRE].

    Article  ADS  Google Scholar 

  78. G.P. Lepage, A new algorithm for adaptive multidimensional integration, J. Comput. Phys. 27 (1978) 192 [INSPIRE].

    Article  ADS  MATH  Google Scholar 

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Correspondence to Ken Mimasu.

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Accomando, E., Mimasu, K. & Moretti, S. Uncovering quasi-degenerate Kaluza-Klein electro-weak gauge bosons with top asymmetries at the LHC. J. High Energ. Phys. 2013, 154 (2013). https://doi.org/10.1007/JHEP07(2013)154

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