- Open Access
Exposing the parton-hadron transition within jets with energy-energy correlators in pp collisions at
Phys. Rev. D 114, 032002 – Published 4 August, 2026
DOI: https://doi.org/10.1103/tgtl-7xh9
Abstract
This paper presents a fully corrected measurement of the energy-energy correlator (EEC) within jets in pp collisions. The EEC traces the energy flow as a highly energetic parton undergoes a QCD shower followed by the confinement of partons into hadrons, probing the correlation function of the energy flow inside jets. The EEC observable is measured as a function of the charged particle pair angular distance, , for . In the perturbative region (large ), a good agreement between the data and a next-to-leading-log perturbative QCD calculation is observed. In the nonperturbative region (small ), the data exhibit a linear dependence. There is a transition region in between, characterized by a turnover in the EEC distribution, indicating where hadronization effects begin to dominate. The peak of this transition region is located at for jets of various energies, indicating a common energy scale for the hadronization process. State-of-the-art Monte Carlo event generators are compared with the measurements, and can be used to constrain the parton shower and hadronization mechanisms.
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