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Quark-gluon discrimination in the search for gluino pair production at the LHC

  • Biplob Bhattacherjee
  • Satyanarayan MukhopadhyayEmail author
  • Mihoko M. Nojiri
  • Yasuhito Sakaki
  • Bryan R. Webber
Open Access
Regular Article - Theoretical Physics

Abstract

We study the impact of including quark- and gluon-initiated jet discrimination in the search for strongly interacting supersymmetric particles at the LHC. Taking the example of gluino pair production, considerable improvement is observed in the LHC search reach on including the jet substructure observables to the standard kinematic variables within a multivariate analysis. In particular, quark and gluon jet separation has higher impact in the region of intermediate mass-gap between the gluino and the lightest neutralino, as the difference between the signal and the standard model background kinematic distributions is reduced in this region. We also compare the predictions from different Monte Carlo event generators to estimate the uncertainty originating from the modelling of the parton shower and hadronization processes.

Keywords

Jets Supersymmetry Phenomenology 

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.

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Copyright information

© The Author(s) 2017

Authors and Affiliations

  • Biplob Bhattacherjee
    • 1
  • Satyanarayan Mukhopadhyay
    • 2
    Email author
  • Mihoko M. Nojiri
    • 3
    • 4
  • Yasuhito Sakaki
    • 5
  • Bryan R. Webber
    • 6
  1. 1.Centre for High Energy Physics, Indian Institute of ScienceBangaloreIndia
  2. 2.PITT-PACC, Department of Physics and AstronomyUniversity of PittsburghPittsburghU.S.A.
  3. 3.Kavli IPMU (WPI), The University of TokyoKashiwaJapan
  4. 4.KEK Theory Center and SokendaiTsukubaJapan
  5. 5.Department of PhysicsKorea Advanced Institute of Science and TechnologyYuseong-guRepublic of Korea
  6. 6.Cavendish LaboratoryCambridgeU.K.

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