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Measuring the bottom-quark forward-central asymmetry at the LHC

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Abstract

Measurements of the top quark forward-backward asymmetry performed at the Tevatron suggest that new-physics may be playing a role in tt production. To better understand the source of the asymmetry, recent proposals have called for a measurement of the bottom and charm forward-backward asymmetries at the Tevatron, using jets with embedded muons. Here we propose a corresponding measurement of the bottom quark forward-central asymmetry designed to look for similar effects in the b-sector at ATLAS and CMS. We construct a set of cuts designed to enhance sensitivity to this asymmetry, and test our analysis on a toy axigluon model representative of those used to explain the top asymmetry. We find that if the relevant new-physics couplings to the bottom quark are similar to those of the top, then the effects should be visible at the 2σ level in less than 10 fb−1 of 7 TeV LHC data. Such a measurement would be of general importance, and would provide valuable model-building input, serving to restrict the set of models put forward to explain the Tevatron tt anomaly. However, a relatively low trigger threshold on non-isolated muons inside hard jets must be maintained to allow for this measurement.

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References

  1. Measurement of the Forward Backward Asymmetry in Top Pair Production in the Dilepton Decay Channel using 5.1 fb −1, CDF note 103098 http://www-cdf.fnal.gov/physics/new/top/2011/DilAfb/.

  2. CDF collaboration, T. Aaltonen et al., Evidence for a Mass Dependent Forward-Backward Asymmetry in Top Quark Pair Production, Phys. Rev. D 83 (2011) 112003 [arXiv:1101.0034] [INSPIRE].

    ADS  Google Scholar 

  3. CDF collaboration, T. Aaltonen et al., Forward-Backward Asymmetry in Top Quark Production in \( p\bar{p} \) Collisions at sqrts = 1.96 TeV, Phys. Rev. Lett. 101 (2008) 202001 [arXiv:0806.2472] [INSPIRE].

    Article  ADS  Google Scholar 

  4. D0 collaboration, V. Abazov et al., First measurement of the forward-backward charge asymmetry in top quark pair production, Phys. Rev. Lett. 100 (2008) 142002 [arXiv:0712.0851] [INSPIRE].

    Article  ADS  Google Scholar 

  5. D0 collaboration, V.M. Abazov et al., Forward-backward asymmetry in top quark-antiquark production, arXiv:1107.4995 [INSPIRE].

  6. 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 

  7. J.H. Kuhn and G. Rodrigo, Charge asymmetry in hadroproduction of heavy quarks, Phys. Rev. Lett. 81 (1998) 49 [hep-ph/9802268] [INSPIRE].

    Article  ADS  Google Scholar 

  8. J.H. Kuhn and G. Rodrigo, Charge asymmetries of top quarks at hadron colliders revisited, arXiv:1109.6830 [INSPIRE].

  9. G. Rodrigo and P. Ferrario, Charge asymmetry: A Theory appraisal, Nuovo Cim. C 33 (2010)04 [arXiv:1007.4328] [INSPIRE].

    Google Scholar 

  10. Measurement of the Charge Asymmetry in Top Quark Pair Production, PAS-TOP-11-014 (Measurement of the Charge Asymmetry in Top Quark Pair Production).

  11. ATLAS collaboration, Measurement of the charge asymmetry in top quark pair production in pp collisions at \( \sqrt {s} = 7TeV \) using the ATLAS detector, ATLAS-CONF-2011-106 (2011).

  12. Y. Bai, J.L. Hewett, J. Kaplan and T.G. Rizzo, LHC Predictions from a Tevatron Anomaly in the Top Quark Forward-Backward Asymmetry, JHEP 03 (2011) 003 [arXiv:1101.5203] [INSPIRE].

    Article  ADS  Google Scholar 

  13. P. Ferrario and G. Rodrigo, Constraining heavy colored resonances from top-antitop quark events, Phys. Rev. D 80 (2009) 051701 [arXiv:0906.5541] [INSPIRE].

    ADS  Google Scholar 

  14. S. Jung, H. Murayama, A. Pierce and J.D. Wells, Top quark forward-backward asymmetry from new t-channel physics, Phys. Rev. D 81 (2010) 015004 [arXiv:0907.4112] [INSPIRE].

    ADS  Google Scholar 

  15. F. del Aguila, J. de Blas, P. Langacker and M. Pérez-Victoria, Impact of extra particles on indirect Z’ limits, Phys. Rev. D 84 (2011) 015015 [arXiv:1104.5512] [INSPIRE].

    ADS  Google Scholar 

  16. G.F. Giudice, B. Gripaios and R. Sundrum, Flavourful Production at Hadron Colliders, JHEP 08 (2011) 055 [arXiv:1105.3161] [INSPIRE].

    Article  ADS  Google Scholar 

  17. A. Djouadi, G. Moreau and F. Richard, Forward-backward asymmetries of the bottom and top quarks in warped extra-dimensional models: LHC predictions from the LEP and Tevatron anomalies, Phys. Lett. B 701 (2011) 458 [arXiv:1105.3158] [INSPIRE].

    ADS  Google Scholar 

  18. R. Barcelo, A. Carmona, M. Masip and J. Santiago, Gluon excitations in t tbar production at hadron colliders, Phys. Rev. D 84 (2011) 014024[arXiv:1105.3333] [INSPIRE].

    ADS  Google Scholar 

  19. C.-H. Chen, S.S. Law and R.-H. Li, Rare B decays and Tevatron top-pair asymmetry, J. Phys. G 38 (2011) 115008 [arXiv:1104.1497] [INSPIRE].

    ADS  Google Scholar 

  20. A.E. Nelson, T. Okui and T.S. Roy, A unified, flavor symmetric explanation for the t-tbar asymmetry and Wjj excess at CDF, Phys. Rev. D 84 (2011) 094007 [arXiv:1104.2030] [INSPIRE].

    ADS  Google Scholar 

  21. X.-P. Wang, Y.-K. Wang, B. Xiao, J. Xu and S.-h. Zhu, New color-octet vector boson revisited, Phys. Rev. D 83 (2011) 115010 [arXiv:1104.1917] [INSPIRE].

  22. C. Degrande, J.-M. Gerard, C. Grojean, F. Maltoni and G. Servant, An Effective approach to same sign top pair production at the LHC and the forward-backward asymmetry at the Tevatron, Phys. Lett. B 703 (2011) 306 [arXiv:1104.1798] [INSPIRE].

    ADS  Google Scholar 

  23. S. Jung, A. Pierce and J.D. Wells, Top quark asymmetry and dijet resonances, Phys. Rev. D 84 (2011)055018 [arXiv:1104.3139] [INSPIRE].

    ADS  Google Scholar 

  24. G. Zhu, B physics constraints on a flavor symmetric scalar model to account for the tt asymmetry and Wjj excess at CDF, Phys. Lett. B 703 (2011) 142 [arXiv:1104.3227] [INSPIRE].

    ADS  Google Scholar 

  25. P.J. Fox, J. Liu, D. Tucker-Smith and N. Weiner, An Effective Z’, Phys. Rev. D 84 (2011) 115006 [arXiv:1104.4127] [INSPIRE].

    ADS  Google Scholar 

  26. D.-W. Jung, P. Ko and J.S. Lee, Possible Common Origin of the Top Forward-backward Asymmetry and the CDF Dijet Resonance, Phys. Rev. D 84 (2011) 055027 [arXiv:1104.4443] [INSPIRE].

    ADS  Google Scholar 

  27. J. Shu, K. Wang and G. Zhu, A Revisit to Top Quark Forward-Backward Asymmetry, arXiv:1104.0083 [INSPIRE].

  28. A. Rajaraman, Z. Surujon and T.M. Tait, Asymmetric Leptons for Asymmetric Tops, arXiv:1104.0947 [INSPIRE].

  29. J. Aguilar-Saavedra and M. Pérez-Victoria, No like-sign tops at Tevatron: Constraints on extended models and implications for the t tbar asymmetry, Phys. Lett. B 701 (2011) 93 [arXiv:1104.1385] [INSPIRE].

    ADS  Google Scholar 

  30. M.R. Buckley, D. Hooper, J. Kopp and E. Neil, Light Z’ Bosons at the Tevatron, Phys. Rev. D 83 (2011) 115013 [arXiv:1103.6035] [INSPIRE].

    ADS  Google Scholar 

  31. S. Jung, A. Pierce and J.D. Wells, Top quark asymmetry from a non-Abelian horizontal symmetry, Phys. Rev. D 83 (2011) 114039 [arXiv:1103.4835] [INSPIRE].

    ADS  Google Scholar 

  32. S. Casagrande, Indirect tests of the Randall-Sundrum model, arXiv:1103.4131 [INSPIRE].

  33. Z. Ligeti, G.M. Tavares and M. Schmaltz, Explaining the t tbar forward-backward asymmetry without dijet or flavor anomalies, JHEP 06 (2011) 109 [arXiv:1103.2757] [INSPIRE].

    Article  ADS  Google Scholar 

  34. C. Grojean, E. Salvioni and R. Torre, A weakly constrained W’ at the early LHC, JHEP 07 (2011)002 [arXiv:1103.2761] [INSPIRE].

    Article  ADS  Google Scholar 

  35. K. Blum, C. Delaunay, O. Gedalia, Y. Hochberg, S.J. Lee, et al., Implications of the CDF \( t\bar{t} \) Forward-Backward Asymmetry for Boosted Top Physics, Phys. Lett. B 702 (2011) 364 [arXiv:1102.3133] [INSPIRE].

    Article  ADS  Google Scholar 

  36. R. Foot, Top quark forward-backward asymmetry from SU(Nc ) color, Phys. Rev. D 83 (2011)114013 [arXiv:1103.1940] [INSPIRE].

    ADS  Google Scholar 

  37. E. Barreto, Y. Coutinho and J. Sa Borges, Top quark forward-backward asymmetry from the 3-3-1 model, Phys. Rev. D 83 (2011) 054006 [arXiv:1103.1266] [INSPIRE].

    ADS  Google Scholar 

  38. A.R. Zerwekh, The Axigluon, a Four-Site Model and the Top Quark Forward-Backward Asymmetry at the Tevatron, Phys. Lett. B 704 (2011) 62 [arXiv:1103.0956] [INSPIRE].

    ADS  Google Scholar 

  39. G. Isidori and J.F. Kamenik, Forward-Backward t tbar Asymmetry from Anomalous Stop Pair Production, Phys. Lett. B 700 (2011) 145 [arXiv:1103.0016] [INSPIRE].

    ADS  Google Scholar 

  40. K.M. Patel and P. Sharma, Forward-backward asymmetry in top quark production from light colored scalars in SO(10) model, JHEP 04 (2011) 085 [arXiv:1102.4736] [INSPIRE].

    Article  ADS  Google Scholar 

  41. B. Grinstein, A.L. Kagan, M. Trott and J. Zupan, Forward-backward asymmetry in tt‾ production from flavour symmetries, Phys. Rev. Lett. 107 (2011) 012002 [arXiv:1102.3374] [INSPIRE].

    Article  ADS  Google Scholar 

  42. V. Barger, W.-Y. Keung and C.-T. Yu, Tevatron Asymmetry of Tops in a W’,Z’ Model, Phys. Lett. B 698 (2011) 243 [arXiv:1102.0279] [INSPIRE].

    ADS  Google Scholar 

  43. J. Shelton and K.M. Zurek, Maximal flavor violation from new right-handed gauge bosons, Phys. Rev. D 83 (2011) 091701 [arXiv:1101.5392] [INSPIRE].

    ADS  Google Scholar 

  44. C. Delaunay, O. Gedalia, S.J. Lee, G. Perez and E. Ponton, Extraordinary Phenomenology from Warped Flavor Triviality, Phys. Lett. B 703 (2011) 486 [arXiv:1101.2902] [INSPIRE].

    ADS  Google Scholar 

  45. K. Cheung and T.-C. Yuan, Top Quark Forward-Backward Asymmetry in the Large Invariant Mass Region, Phys. Rev. D 83 (2011) 074006 [arXiv:1101.1445] [INSPIRE].

    ADS  Google Scholar 

  46. Y. Cui, Z. Han and M.D. Schwartz, Top condensation as a motivated explanation of the top forward-backward asymmetry, JHEP 07 (2011) 127 [arXiv:1106.3086] [INSPIRE].

    Article  ADS  Google Scholar 

  47. G.M. Tavares and M. Schmaltz, Explaining the t-tbar asymmetry with a light axigluon, Phys. Rev. D 84 (2011) 054008 [arXiv:1107.0978] [INSPIRE].

    ADS  Google Scholar 

  48. J. Aguilar-Saavedra and M. Pérez-Victoria, Shaping the top asymmetry, Phys. Lett. B 705 (2011)228 [arXiv:1107.2120] [INSPIRE].

    ADS  Google Scholar 

  49. U. Haisch and S. Westhoff, Massive Color-Octet Bosons: Bounds on Effects in Top-Quark Pair Production, JHEP 08 (2011) 088 [arXiv:1106.0529] [INSPIRE].

    Article  ADS  Google Scholar 

  50. M. Bauer, F. Goertz, U. Haisch, T. Pfoh and S. Westhoff, Top-Quark Forward-Backward Asymmetry in Randall-Sundrum Models Beyond the Leading Order, JHEP 11 (2010) 039 [arXiv:1008.0742] [INSPIRE].

    Article  ADS  Google Scholar 

  51. J.F. Kamenik, J. Shu and J. Zupan, Review of new physics effects in t-tbar production, arXiv:1107.5257 [INSPIRE].

  52. CMS collaboration, S. Chatrchyan et al., Search for Same-Sign Top-Quark Pair Production at sqrt(s) = 7 TeV and Limits on Flavour Changing Neutral Currents in the Top Sector, JHEP 08 (2011) 005 [arXiv:1106.2142] [INSPIRE].

    Article  ADS  Google Scholar 

  53. M.I. Gresham, I.-W. Kim and K.M. Zurek, On Models of New Physics for the Tevatron Top AF B , Phys. Rev. D 83 (2011) 114027 [arXiv:1103.3501] [INSPIRE].

    ADS  Google Scholar 

  54. M.I. Gresham, I.-W. Kim and K.M. Zurek, Tevatron Top AF B Versus LHC Top Physics, arXiv:1107.4364 [INSPIRE].

  55. Y.-k. Wang, B. Xiao and S.-h. Zhu, One-side Forward-backward Asymmetry in Top Quark Pair Production at CERN Large Hadron Collider, Phys. Rev. D 82 (2010) 094011 [arXiv:1008.2685] [INSPIRE].

    ADS  Google Scholar 

  56. J.L. Hewett, J. Shelton, M. Spannowsky, T.M. Tait and M. Takeuchi, AF B Meets LHC, Phys. Rev. D 84 (2011) 054005 [arXiv:1103.4618] [INSPIRE].

    ADS  Google Scholar 

  57. B. Xiao, Y.-K. Wang, Z.-Q. Zhou and S.-h. Zhu, Edge Charge Asymmetry in Top Pair Production at the LHC, Phys. Rev. D 83 (2011) 057503 [arXiv:1101.2507] [INSPIRE].

    ADS  Google Scholar 

  58. B. Bhattacherjee, S.S. Biswal and D. Ghosh, Top quark forward-backward asymmetry at Tevatron and its implications at the LHC, Phys. Rev. D 83 (2011) 091501 [arXiv:1102.0545] [INSPIRE].

    ADS  Google Scholar 

  59. J. Aguilar-Saavedra and M. Pérez-Victoria, Asymmetries in t t production: LHC versus Tevatron, arXiv:1105.4606 [INSPIRE].

  60. E.L. Berger, Q.-H. Cao, C.-R. Chen and H. Zhang, Top Quark Polarization As A Probe of Models with Extra Gauge Bosons, Phys. Rev. D 83 (2011) 114026 [arXiv:1103.3274] [INSPIRE].

    ADS  Google Scholar 

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

    Article  ADS  Google Scholar 

  62. J. Cao, L. Wu and J.M. Yang, New physics effects on top quark spin correlation and polarization at the LHC: a comparative study in different models, Phys. Rev. D 83 (2011) 034024 [arXiv:1011.5564] [INSPIRE].

    ADS  Google Scholar 

  63. D.-W. Jung, P. Ko and J.S. Lee, Longitudinal top polarization as a probe of a possible origin of forward-backward asymmetry of the top quark at the Tevatron, Phys. Lett. B 701 (2011) 248 [arXiv:1011.5976] [INSPIRE].

    ADS  Google Scholar 

  64. D. Choudhury, R.M. Godbole, S.D. Rindani and P. Saha, Top polarization, forward-backward asymmetry and new physics, Phys. Rev. D 84 (2011) 014023 [arXiv:1012.4750] [INSPIRE].

    ADS  Google Scholar 

  65. W. Bernreuther and Z.-G. Si, Distributions and correlations for top quark pair production and decay at the Tevatron and LHC., Nucl. Phys. B 837 (2010) 90 [arXiv:1003.3926] [INSPIRE].

    Article  ADS  Google Scholar 

  66. K. Melnikov and M. Schulze, NLO QCD corrections to top quark pair production and decay at hadron colliders, JHEP 08 (2009) 049 [arXiv:0907.3090] [INSPIRE].

    Article  ADS  Google Scholar 

  67. 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 

  68. Y. Bai and Z. Han, Improving the Top Quark Forward-Backward Asymmetry Measurement at the LHC, Journal of High Energy Physics (JHEP) (2011) [arXiv:1106.5071] [INSPIRE].

  69. M.I. Gresham, I.-W. Kim and K.M. Zurek, Searching for Top Flavor Violating Resonances, Phys. Rev. D 84 (2011) 034025 [arXiv:1102.0018] [INSPIRE].

    ADS  Google Scholar 

  70. N. Craig, C. Kilic and M.J. Strassler, LHC Charge Asymmetry as Constraint on Models for the Tevatron Top Anomaly, Phys. Rev. D 84 (2011) 035012 [arXiv:1103.2127] [INSPIRE].

    ADS  Google Scholar 

  71. J. Cao, L. Wang, L. Wu and J.M. Yang, Top quark forward-backward asymmetry, FCNC decays and like-sign pair production as a joint probe of new physics, Phys. Rev. D 84 (2011) 074001 [arXiv:1101.4456] [INSPIRE].

    ADS  Google Scholar 

  72. E. Alvarez, L. Da Rold, J.I.S. Vietto and A. Szynkman, Phenomenology of a light gluon resonance in top-physics at Tevatron and LHC, JHEP 09 (2011) 007 [arXiv:1107.1473] [INSPIRE].

    Article  ADS  Google Scholar 

  73. E.L. Berger, Q.-H. Cao, C.-R. Chen, C.S. Li and H. Zhang, Top Quark Forward-Backward Asymmetry and Same-Sign Top Quark Pairs, Phys. Rev. Lett. 106 (2011) 201801 [arXiv:1101.5625] [INSPIRE].

    Article  ADS  Google Scholar 

  74. M.J. Strassler, A Note on Measuring Charm and Bottom Forward-Backward Asymmetries at the Tevatron, arXiv:1102.0736 [INSPIRE].

  75. Y.-k. Wang, B. Xiao and S.-h. Zhu, One-side forward-backward asymmetry at the LHC, Phys. Rev. D 83 (2011) 015002 [arXiv:1011.1428] [INSPIRE].

    ADS  Google Scholar 

  76. L.M. Sehgal and M. Wanninger, Forward - Backward Asymmetry In Two Jet Events: Signature Of Axigluons In Proton - Anti-proton Collisions, Phys. Lett. B 200 (1988) 211 [INSPIRE].

    ADS  Google Scholar 

  77. J. Alwall et al., MadGraph/MadEvent v4: The New Web Generation, JHEP 09 (2007) 028 [arXiv:0706.2334] [INSPIRE].

    Article  ADS  Google Scholar 

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

    Article  ADS  Google Scholar 

  79. 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 

  80. M. Cacciari, G. Salam and G. Soyez, FastJet, http://fastjet.fr/.

  81. M. Cacciari and G.P. Salam, Dispelling the N 3 myth for the kt jet-finder, Phys. Lett. B 641 (2006)57 [hep-ph/0512210] [INSPIRE].

    ADS  Google Scholar 

  82. M. Cacciari, G.P. Salam and G. Soyez, The Anti-k(t) jet clustering algorithm, JHEP 04 (2008) 063 [arXiv:0802.1189] [INSPIRE].

    Article  ADS  Google Scholar 

  83. The ATLAS collaboration, G. Aad et al., Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics, arXiv:0901.0512 [INSPIRE].

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Authors and Affiliations

  1. Department of Physics, Harvard University, Cambridge, MA, 02138, U.S.A

    Dilani Kahawala & David Krohn

  2. New High Energy Theory Center, Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Rd, Piscataway, NJ, 08854, U.S.A

    Matthew J. Strassler

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  1. Dilani Kahawala
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  2. David Krohn
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  3. Matthew J. Strassler
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Correspondence to David Krohn.

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Kahawala, D., Krohn, D. & Strassler, M.J. Measuring the bottom-quark forward-central asymmetry at the LHC. J. High Energ. Phys. 2012, 69 (2012). https://doi.org/10.1007/JHEP01(2012)069

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