Journal of High Energy Physics

, 2014:154 | Cite as

Cornering scalar leptoquarks at LHC

  • Ilja DoršnerEmail author
  • Svjetlana Fajfer
  • Admir Greljo
Open Access


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.


Phenomenological Models Hadronic Colliders 


Open Access

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Copyright information

© The Author(s) 2014

Authors and Affiliations

  • Ilja Doršner
    • 1
    Email author
  • 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

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