Probing stop pair production at the LHC with graph neural networks

  • Murat Abdughani
  • Jie Ren
  • Lei WuEmail author
  • Jin Min Yang
Open Access
Regular Article - Theoretical Physics


Top-squarks (stops) play a crucial role for the naturalness of supersymmetry (SUSY). However, searching for the stops is a tough task at the LHC. To dig the stops out of the huge LHC data, various expert-constructed kinematic variables or cutting-edge analysis techniques have been invented. In this paper, we propose to represent collision events as event graphs and use the message passing neutral network (MPNN) to analyze the events. As a proof-of-concept, we use our method in the search of the stop pair production at the LHC, and find that our MPNN can efficiently discriminate the signal and back-ground events. In comparison with other machine learning methods (e.g. DNN), MPNN can enhance the mass reach of stop mass by several tens of GeV to over a hundred GeV.


Supersymmetry Phenomenology 


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) 2019

Authors and Affiliations

  1. 1.Department of Physics and Institute of Theoretical PhysicsNanjing Normal UniversityNanjingChina
  2. 2.CAS Key Laboratory of Theoretical Physics, Institute of Theoretical PhysicsChinese Academy of SciencesBeijingChina
  3. 3.School of PhysicsUniversity of Chinese Academy of SciencesBeijingChina
  4. 4.Department of PhysicsTohoku UniversitySendaiJapan

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