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Study of quark and gluon jet identification in photoproduction at the EIC

Siddharth Narayan Singh*

R. Aggarwal†

M. Kaur‡

  • *Contact author: siddharthsingh@brandeis.edu
  • †Contact author: ritu.aggarwal1@gmail.com
  • ‡Contact author: manjit@pu.ac.in
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Phys. Rev. D 114, 036009 – Published 10 August, 2026

DOI: https://doi.org/10.1103/v28z-qw9b

Abstract

This paper presents a systematic study of the substructure of dijets produced in direct and resolved photoproduction events and subsequent quark and gluon jet identification in dijets, considering the kinematic reach of the upcoming Electron-Ion Collider (EIC) experiment. We investigate the substructure of jets produced in dijet photoproduction events with center-of-mass energies s=64–140  GeV at the EIC. Events are simulated using event generator pythia and contributions from direct and resolved photoproduction subprocesses are analyzed at different energies. Jets are reconstructed using longitudinally invariant kT algorithm within the fastjet framework. Substructure of quark and gluon initiated jets in the selected dijet photoproduction sample is studied in detail by using jet-shape variables. Predictions for subjet multiplicities and integrated jet shapes are presented in the gluon-initiated and quark-initiated jets in the dijet photoproduction events at the EIC energies. These results demonstrate the feasibility of distinguishing quark and gluon jets in the photoproduction events at the EIC and provide a baseline for further QCD studies.

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Outline

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Phys. Rev. D 114, 036009– Published 10 August, 2026
  • Received 16 March 2026
  • Revised 27 May 2026
  • Accepted 6 July 2026
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