Lepton flavor violating dilepton dijet signatures from sterile neutrinos at proton colliders

  • Stefan Antusch
  • Eros Cazzato
  • Oliver Fischer
  • A. Hammad
  • Kechen WangEmail author
Open Access
Regular Article - Theoretical Physics


In this article we investigate the prospects of searching for sterile neutrinos in lowscale seesaw scenarios via the lepton flavour violating (but lepton number conserving) dilepton dijet signature. In our study, we focus on the final state e±μjj at the HL-LHC and the FCC-hh (or the SppC). We perform a multivariate analysis at the detector level including the dominant SM backgrounds from di-top, di-boson, and tri-boson. Under the assumption of the active-sterile neutrino mixings |VlN|2 = |θe|2 = |θμ|2 and |VτN|2 = |θτ|2 = 0, the sensitivities on the signal production cross section times branching ratio σ(ppl±N) × BR(Nljj) and on |VlN|2 for sterile neutrino mass MN between 200 and 1000 GeV are derived. For the benchmark MN = 500 GeV, when ignoring systematic uncertainties at the HL-LHC (FCC-hh/SppC) with 3 (20) ab−1 luminosity, the resulting 2-σ limits on |VlN|2 are 4.9 × 10−3 (7.0 × 10−5), while the 2-σ limit on σ × BR are 4.4 × 10−2 (1.6 × 10−2) fb, respectively. The effect of the systematic uncertainty is also studied and found to be important for sterile neutrinos with smaller masses. We also comment on searches with τ±μjj and τ±ejj final states.


Phenomenological Models 


Open Access

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  1. 1.Department of PhysicsUniversity of BaselBaselSwitzerland
  2. 2.Institute for Nuclear PhysicsKarlsruhe Institute of TechnologyEggenstein-LeopoldshafenGermany
  3. 3.DESYHamburgGermany
  4. 4.Center for Future High Energy Physics, Institute of High Energy PhysicsChinese Academy of SciencesBeijingChina

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