Advertisement

Journal of High Energy Physics

, 2014:154 | Cite as

Cornering scalar leptoquarks at LHC

Open Access
Article

Abstract

We study implications of large lepton-quark-leptoquark couplings for direct leptoquark searches at Large Hadron Collider. We present all existing flavor constraints on the strength of these couplings assuming that leptoquarks under consideration interact exclusively with charged leptons and quarks of the same generation. We find that these leptoquarks can have sizeable couplings to the Standard Model fermions. This insures a self consistency of our study. We discuss the leptoquark production mechanisms at LHC and demonstrate the importance of inclusion of a t-channel pair production and, in particular, a single leptoquark production through a recast of an existing CMS search at LHC for the second generation leptoquark. Our recast yields the best direct limit on Yukawa coupling of the second generation leptoquark that couples to a muon and a strange quark to date.

Keywords

Phenomenological Models Hadronic Colliders 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

References

  1. [1]
    J.C. Pati and A. Salam, Lepton number as the fourth color, Phys. Rev. D 10 (1974) 275 [Erratum ibid. D 11 (1975) 703] [INSPIRE].
  2. [2]
    H. Georgi and S.L. Glashow, Unity of all elementary particle forces, Phys. Rev. Lett. 32 (1974) 438 [INSPIRE].ADSCrossRefGoogle Scholar
  3. [3]
    W. Buchmüller, R. Ruckl and D. Wyler, Leptoquarks in lepton-quark collisions, Phys. Lett. B 191 (1987) 442 [Erratum ibid. B 448 (1999) 320] [INSPIRE].
  4. [4]
    J.L. Hewett and S. Pakvasa, Leptoquark production in hadron colliders, Phys. Rev. D 37 (1988) 3165 [INSPIRE].ADSGoogle Scholar
  5. [5]
    O.J.P. Eboli and A.V. Olinto, Composite leptoquarks in hadronic colliders, Phys. Rev. D 38 (1988) 3461 [INSPIRE].ADSGoogle Scholar
  6. [6]
    M. De Montigny and L. Marleau, Production of leptoquark scalars in hadron colliders, Phys. Rev. D 40 (1989) 2869 [Erratum ibid. D 56 (1997) 3156] [INSPIRE].
  7. [7]
    J. Ohnemus, S. Rudaz, T.F. Walsh and P.M. Zerwas, Single leptoquark production at hadron colliders, Phys. Lett. B 334 (1994) 203 [hep-ph/9406235] [INSPIRE].ADSCrossRefGoogle Scholar
  8. [8]
    O.J.P. Eboli and T.L. Lungov, Single production of leptoquarks at the Tevatron, Phys. Rev. D 61 (2000) 075015 [hep-ph/9911292] [INSPIRE].ADSGoogle Scholar
  9. [9]
    A. Belyaev, C. Leroy, R. Mehdiyev and A. Pukhov, Leptoquark single and pair production at LHC with CalcHEP/CompHEP in the complete model, JHEP 09 (2005) 005 [hep-ph/0502067] [INSPIRE].ADSCrossRefGoogle Scholar
  10. [10]
    I. Doršner, S. Fajfer and N. Kosnik, Heavy and light scalar leptoquarks in proton decay, Phys. Rev. D 86 (2012) 015013 [arXiv:1204.0674] [INSPIRE].ADSGoogle Scholar
  11. [11]
    S. Davidson and S. Descotes-Genon, Minimal flavour violation for leptoquarks, JHEP 11 (2010) 073 [arXiv:1009.1998] [INSPIRE].ADSCrossRefMATHGoogle Scholar
  12. [12]
    H1 collaboration, F.D. Aaron et al., Search for lepton flavour violation at HERA, Phys. Lett. B 701 (2011) 20 [arXiv:1103.4938] [INSPIRE].ADSGoogle Scholar
  13. [13]
    J. Alwall, M. Herquet, F. Maltoni, O. Mattelaer and T. Stelzer, MadGraph 5: going beyond, JHEP 06 (2011) 128 [arXiv:1106.0522] [INSPIRE].ADSCrossRefMATHGoogle Scholar
  14. [14]
    N.D. Christensen and C. Duhr, FeynRulesFeynman rules made easy, Comput. Phys. Commun. 180 (2009) 1614 [arXiv:0806.4194] [INSPIRE].ADSCrossRefGoogle Scholar
  15. [15]
    M.I. Gresham, I.-W. Kim, S. Tulin and K.M. Zurek, Confronting top AFB with parity violation constraints, Phys. Rev. D 86 (2012) 034029 [arXiv:1203.1320] [INSPIRE].ADSGoogle Scholar
  16. [16]
    M.J. Ramsey-Musolf, Low-energy parity violation and new physics, Phys. Rev. C 60 (1999) 015501 [hep-ph/9903264] [INSPIRE].ADSGoogle Scholar
  17. [17]
    W.J. Marciano and A. Sirlin, Radiative corrections to atomic parity violation, Phys. Rev. D 27 (1983) 552 [INSPIRE].ADSGoogle Scholar
  18. [18]
    C.S. Wood et al., Measurement of parity nonconservation and an anapole moment in cesium, Science 275 (1997) 1759 [INSPIRE].CrossRefGoogle Scholar
  19. [19]
    J. Guena, M. Lintz and M.A. Bouchiat, Measurement of the parity violating 6S-7S transition amplitude in cesium achieved within 2 × 10−13 atomic-unit accuracy by stimulated-emission detection, Phys. Rev. A 71 (2005) 042108 [physics/0412017] [INSPIRE].ADSCrossRefGoogle Scholar
  20. [20]
    S.G. Porsev, K. Beloy and A. Derevianko, Precision determination of electroweak coupling from atomic parity violation and implications for particle physics, Phys. Rev. Lett. 102 (2009) 181601 [arXiv:0902.0335] [INSPIRE].ADSCrossRefGoogle Scholar
  21. [21]
    I. Doršner, J. Drobnak, S. Fajfer, J.F. Kamenik and N. Kosnik, Limits on scalar leptoquark interactions and consequences for GUTs, JHEP 11 (2011) 002 [arXiv:1107.5393] [INSPIRE].ADSCrossRefMATHGoogle Scholar
  22. [22]
    S. Aoki et al., Review of lattice results concerning low-energy particle physics, Eur. Phys. J. C 74 (2014) 2890 [arXiv:1310.8555] [INSPIRE].ADSCrossRefGoogle Scholar
  23. [23]
    Particle Data Group collaboration, J. Beringer et al., Review of particle physics (RPP), Phys. Rev. D 86 (2012) 010001 [INSPIRE].Google Scholar
  24. [24]
    H. Na, C.T.H. Davies, E. Follana, G.P. Lepage and J. Shigemitsu, |V cd| from D meson leptonic decays, Phys. Rev. D 86 (2012) 054510 [arXiv:1206.4936] [INSPIRE].ADSGoogle Scholar
  25. [25]
    K.-M. Cheung, Muon anomalous magnetic moment and leptoquark solutions, Phys. Rev. D 64 (2001) 033001 [hep-ph/0102238] [INSPIRE].ADSGoogle Scholar
  26. [26]
    I. Doršner, S. Fajfer, N. Košnik and I. Nišandžić, Minimally flavored colored scalar in \( \overline{B}\to {D}^{\left(*\right)}\tau \overline{\nu} \) and the mass matrices constraints, JHEP 11 (2013) 084 [arXiv:1306.6493] [INSPIRE].ADSCrossRefGoogle Scholar
  27. [27]
    F.S. Queiroz and W. Shepherd, New physics contributions to the muon anomalous magnetic moment: a numerical code, Phys. Rev. D 89 (2014) 095024 [arXiv:1403.2309] [INSPIRE].ADSGoogle Scholar
  28. [28]
    CMS collaboration, Search for pair-production of second generation leptoquarks in 8 TeV proton-proton collisions., CMS-PAS-EXO-12-042, CERN, Geneva Switzerland (2012).
  29. [29]
    M. Krämer, T. Plehn, M. Spira and P.M. Zerwas, Pair production of scalar leptoquarks at the CERN LHC, Phys. Rev. D 71 (2005) 057503 [hep-ph/0411038] [INSPIRE].ADSGoogle Scholar
  30. [30]
    T. Sjöstrand, S. Mrenna and P.Z. Skands, PYTHIA 6.4 physics and manual, JHEP 05 (2006) 026 [hep-ph/0603175] [INSPIRE].ADSCrossRefMATHGoogle Scholar
  31. [31]
    DELPHES 3 collaboration, J. de Favereau et al., DELPHES 3, a modular framework for fast simulation of a generic collider experiment, JHEP 02 (2014) 057 [arXiv:1307.6346] [INSPIRE].ADSGoogle Scholar

Copyright information

© The Author(s) 2014

Authors and Affiliations

  • Ilja Doršner
    • 1
  • Svjetlana Fajfer
    • 2
    • 3
  • Admir Greljo
    • 2
  1. 1.Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture in Split (FESB)University of SplitSplitCroatia
  2. 2.J. Stefan InstituteLjubljanaSlovenia
  3. 3.Department of PhysicsUniversity of LjubljanaLjubljanaSlovenia

Personalised recommendations