- Open Access
Energy-energy correlators inside single inclusive jets in heavy-ion collisions with the CoLBT-hydro model
Phys. Rev. C 114, 034914 – Published 21 September, 2026
DOI: https://doi.org/10.1103/zpvs-4x68
Abstract
The energy-energy correlator (EEC) inside jets is a sensitive observable for studying jet modification in the quark-gluon plasma. However, its interpretation in heavy-ion collisions remains challenging, requiring a consistent understanding of jet evolution across multiple dynamical scales together with a proper treatment of the background subtraction. In this work, we employ an updated CoLBT-hydro framework in which a medium scale GeV is introduced to separate the vacuum and in-medium stages of the parton shower, enabling a more self-consistent treatment of jet evolution. Using a theoretical background subtraction within the model, the resulting simulation reproduces the recent CMS measurement of the in-jet EEC and, through a decomposition of the different contributions, highlights the impact of medium modification on the observable. To further validate the experimental procedure, we also implement the CMS mixed-event background-subtraction method directly in the simulation and find that the results are consistent with those obtained with the theoretical background subtraction. Using -ranked jets in each event, we further investigate the dependence of medium modification on the in-medium path length, reflected in the different EECs of leading and subleading jets. Finally, we explore the dependence of the leading-jet EEC on the dijet rapidity gap as a signal of the jet-induced diffusion wake.
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References (112)
- J. D. Bjorken, Energy loss of energetic partons in quark-gluon plasma: Possible extinction of high- jets in hadron-hadron collisions, Technical Report No. FERMILAB-PUB-82-059-THY, Fermi National Accelerator Laboratory, Batavia, Illinois, 1982.
- M. H. Thoma and M. Gyulassy, Quark damping and energy loss in the high temperature QCD, Nucl. Phys. B 351, 491 (1991).
- E. Braaten and M. H. Thoma, Energy loss of a heavy quark in the quark-gluon plasma, Phys. Rev. D 44, R2625 (1991).
- M. Gyulassy and X.-N. Wang, Multiple collisions and induced gluon bremsstrahlung in QCD, Nucl. Phys. B 420, 583 (1994).
- R. Baier, Y. L. Dokshitzer, A. H. Mueller, S. Peigne, and D. Schiff, Radiative energy loss of high-energy quarks and gluons in a finite volume quark-gluon plasma, Nucl. Phys. B 483, 291 (1997).
- B. G. Zakharov, Fully quantum treatment of the Landau-Pomeranchuk-Migdal effect in QED and QCD, JETP Lett. 63, 952 (1996).
- M. Gyulassy, P. Levai, and I. Vitev, Jet quenching in thin quark gluon plasmas. 1. Formalism, Nucl. Phys. B 571, 197 (2000).
- U. A. Wiedemann, Gluon radiation off hard quarks in a nuclear environment: Opacity expansion, Nucl. Phys. B 588, 303 (2000).
- X.-N. Wang and X.-F. Guo, Multiple parton scattering in nuclei: Parton energy loss, Nucl. Phys. A 696, 788 (2001).
- P. B. Arnold, G. D. Moore, and L. G. Yaffe, Photon and gluon emission in relativistic plasmas, J. High Energy Phys. 06 (2002) 030.
- M. Djordjevic, Collisional energy loss in a finite size QCD matter, Phys. Rev. C 74, 064907 (2006).
- G.-Y. Qin, J. Ruppert, C. Gale, S. Jeon, G. D. Moore, and M. G. Mustafa, Radiative and collisional jet energy loss in the quark-gluon plasma at RHIC, Phys. Rev. Lett. 100, 072301 (2008).
- X.-N. Wang and U. A. Wiedemann, QGP@50: More than four decades of jet quenching, arXiv:2508.18794.
- K. Adcox et al. (PHENIX Collaboration), Suppression of hadrons with large transverse momentum in central Au+Au collisions at = 130 GeV, Phys. Rev. Lett. 88, 022301 (2001).
- C. Adler et al. (STAR Collaboration), Centrality dependence of high- hadron suppression in Au + Au collisions at = 130 GeV, Phys. Rev. Lett. 89, 202301 (2002).
- M. Gyulassy and L. McLerran, New forms of QCD matter discovered at RHIC, Nucl. Phys. A 750, 30 (2005).
- X.-N. Wang, Discovery of jet quenching and beyond, Nucl. Phys. A 750, 98 (2005).
- K. Aamodt et al. (ALICE Collaboration), Suppression of charged particle production at large transverse momentum in central Pb-Pb collisions at 2.76 TeV, Phys. Lett. B 696, 30 (2011).
- G. Aad et al. (ATLAS Collaboration), Observation of a centrality-dependent dijet asymmetry in lead-lead collisions at TeV with the ATLAS detector at the LHC, Phys. Rev. Lett. 105, 252303 (2010).
- A. Majumder and M. Van Leeuwen, The theory and phenomenology of perturbative QCD based jet quenching, Prog. Part. Nucl. Phys. 66, 41 (2011).
- S. Chatrchyan et al. (CMS Collaboration), Observation and studies of jet quenching in PbPb collisions at nucleon-nucleon center-of-mass energy = 2.76 TeV, Phys. Rev. C 84, 024906 (2011).
- G.-Y. Qin and X.-N. Wang, Jet quenching in high-energy heavy-ion collisions, Int. J. Mod. Phys. E 24, 1530014 (2015).
- L. Apolinário, Y.-T. Chien, and L. Cunqueiro Mendez, Jet substructure, Int. J. Mod. Phys. E 33, 2430003 (2024).
- C. L. Basham, L. S. Brown, S. D. Ellis, and S. T. Love, Electron-positron annihilation energy pattern in quantum chromodynamics: Asymptotically free perturbation theory, Phys. Rev. D 17, 2298 (1978).
- C. L. Basham, L. S. Brown, S. D. Ellis, and S. T. Love, Energy correlations in electron-positron annihilation: Testing QCD, Phys. Rev. Lett. 41, 1585 (1978).
- C. L. Basham, L. S. Brown, S. D. Ellis, and S. T. Love, Energy correlations in electron-positron annihilation in quantum chromodynamics: Asymptotically free perturbation theory, Phys. Rev. D 19, 2018 (1979).
- P. T. Komiske, I. Moult, J. Thaler, and H. X. Zhu, Analyzing N-point energy correlators inside jets with CMS open data, Phys. Rev. Lett. 130, 051901 (2023).
- I. Moult and H. X. Zhu, Energy correlators: A journey from theory to experiment, arXiv:2506.09119.
- C. Andres, F. Dominguez, R. Kunnawalkam Elayavalli, J. Holguin, C. Marquet, and I. Moult, Resolving the scales of the quark-gluon plasma with energy correlators, Phys. Rev. Lett. 130, 262301 (2023).
- Z. Yang, Y. He, I. Moult, and X.-N. Wang, Probing the short-distance structure of the quark-gluon plasma with energy correlators, Phys. Rev. Lett. 132, 011901 (2024).
- J. Barata, P. Caucal, A. Soto-Ontoso, and R. Szafron, Advancing the understanding of energy-energy correlators in heavy-ion collisions, J. High Energy Phys. 11 (2024) 060.
- C. Andres, F. Dominguez, J. Holguin, C. Marquet, and I. Moult, A coherent view of the quark-gluon plasma from energy correlators, J. High Energy Phys. 09 (2023) 088.
- C. Andres, F. Dominguez, J. Holguin, C. Marquet, and I. Moult, Seeing beauty in the quark-gluon plasma with energy correlators, Phys. Rev. D 110, L031503 (2024).
- J. Barata, Z.-B. Kang, X. Mayo López, and J. Penttala, Energy-energy correlator for jet production in pp and pA collisions, Phys. Rev. Lett. 134, 251903 (2025).
- Y. Fu, B. Müller, and C. Sirimanna, Modification of the jet energy-energy correlator in cold nuclear matter, Phys. Rev. Lett. 135, 112302 (2025).
- C. Andres, F. Dominguez, J. Holguin, C. Marquet, and I. Moult, Simple scaling laws for energy correlators in nuclear matter, Phys. Rev. Lett. 136, 122301 (2026).
- W.-J. Xing, S. Cao, G.-Y. Qin, and X.-N. Wang, Flavor hierarchy of jet energy correlators inside the quark-gluon plasma, Phys. Rev. Lett. 134, 052301 (2025).
- B. Singh and V. Vaidya, Factorization for energy-energy correlator in heavy ion collision, J. High Energy Phys. 06 (2025) 071.
- H. Bossi, A. S. Kudinoor, I. Moult, D. Pablos, A. Rai, and K. Rajagopal, Imaging the wakes of jets with energy-energy-energy correlators, J. High Energy Phys. 12 (2024) 073.
- C. Andres, J. Holguin, R. Kunnawalkam Elayavalli, and J. Viinikainen, Minimizing selection bias in inclusive jets in heavy-ion collisions with energy correlators, Phys. Rev. Lett. 134, 082303 (2025).
- J. Barata, M. V. Kuzmin, J. G. Milhano, and A. V. Sadofyev, Giving wake to energy-energy correlators: Hydrodynamic response on the celestial sphere, Phys. Rev. D 112, 016005 (2025).
- W. Ke, B. Mecaj, and I. Vitev, Renormalization group evolution for in-medium energy correlators, J. High Energy Phys. 04 (2026) 155.
- M.-Q. Yang, P. Ru, and B.-W. Zhang, Multiprocess imaging of nuclear modifications on parton distributions in proton-nucleus collisions, Phys. Rev. D 112, 074008 (2025).
- J. Barata, J. Brewer, K. Lee, and J. M. Silva, Heavy quark pair energy correlators: From profiling partonic splittings to probing heavy-flavor fragmentation, arXiv:2508.19404.
- J. Barata, D. Frenklakh, and S. Mukherjee, Thermal modifications of mesons and energy-energy correlators from real-time simulations of a U(1) lattice gauge theory, Phys. Rev. D 112, 114505 (2025).
- A. Budhraja and B. Singh, Exploiting -dependence of projected energy correlators in HICs, Phys. Lett. B 872, 140079 (2026).
- J. Barata, I. Moult, A. V. Sadofyev, and J. M. Silva, Dissecting jet modification in the quark-gluon plasma with multipoint energy correlators, Phys. Rev. Lett. 137, 052302 (2026).
- H.-Y. Liu, S.-Y. Chen, W. Dai, B.-W. Zhang, and E. Wang, The medium modification of the charge-weighted energy-energy correlators in Pb+Pb collisions at TeV, Chin. Phys. C 50, 074103 (2026).
- L. Apolinário, R. Kunnawalkam Elayavalli, N. O. Madureira, J.-X. Sheng, X.-N. Wang, and Z. Yang, Flavor dependence of energy-energy correlators, Phys. Rev. D 112, 054018 (2025).
- C. Andres, J. Holguin, B. Kimelman, R. Kunnawalkam Elayavalli, J. Viinikainen, and Z. Yang, Living on the edge: Radius effects in the angular substructure of heavy-ion jets, arXiv:2512.10026.
- S. Acharya et al. (ALICE Collaboration), Exposing the parton-hadron transition within jets with energy-energy correlators in collisions at TeV, Phys. Rev. D 114, 032002 (2026).
- A. Hayrapetyan et al. (CMS Collaboration), Measurement of energy correlators inside jets and determination of the strong coupling (mZ), Phys. Rev. Lett. 133, 071903 (2024).
- B. E. Aboona et al. (STAR Collaboration), Measurement of two-point energy correlators within jets in collisions at = 200 GeV, Phys. Rev. Lett. 135, 111901 (2025).
- S. Acharya et al. (ALICE Collaboration), Energy-energy correlators in charm-tagged jets in proton-proton collisions at TeV, arXiv:2504.03431.
- V. Chekhovsky et al. (CMS Collaboration), Observation of nuclear modification of energy-energy correlators inside jets in heavy ion collisions, Phys. Lett. B 866, 139556 (2025).
- , Energy-energy correlation in Z boson tagged PbPb and pp collisions at = 5.02 TeV, Technical Report No. CMS-PAS-HIN-24-019, CERN, Geneva, Switzerland, 2025.
- A. Nambrath, Energy-energy correlators in jets across collision systems and parton flavors, EPJ Web Conf. 339, 02001 (2025).
- X. Liu, W. Vogelsang, F. Yuan, and H. X. Zhu, Universality in the near-side energy-energy correlator, Phys. Rev. Lett. 134, 151901 (2025).
- J. Barata and S. Mukherjee, Probing celestial energy and charge correlations through real-time quantum simulations: Insights from the Schwinger model, Phys. Rev. D 111, L031901 (2025).
- K. Lee, F. Turro, and X. Yao, Quantum computing for energy correlators, Phys. Rev. D 111, 054514 (2025).
- M. Jaarsma, Y. Li, I. Moult, W. J. Waalewijn, and H. X. Zhu, From DGLAP to Sudakov: Precision predictions for energy-energy correlators, arXiv:2512.11950.
- Y. Guo, W. Vogelsang, F. Yuan, and W. Zhao, Energy-energy correlators in annihilation and deep inelastic scattering, Phys. Rev. D 113, 074027 (2026).
- Y. Guo, F. Yuan, and W. Zhao, Factorization and resummation for the nearside energy-energy correlators, Phys. Rev. Lett. 136, 081904 (2026).
- H. Chen, H. Ruan, and H. X. Zhu, Energy-energy correlator at hadron colliders: Celestial blocks and singularities, J. High Energy Phys. 12 (2025) 168.
- H. Bossi, Y.-C. Chen, Y. Chen, J. Zhang, G. M. Innocenti, A. Badea, A. Baty, M. Maggi, C. McGinn, and Y.-J. Lee, Analysis note: Measurement of energy-energy correlator in collisions at 91 GeV with archived ALEPH data, arXiv:2505.11828.
- S. Alipour-fard and W. J. Waalewijn, Energy correlators beyond angles, J. High Energy Phys. 07 (2025) 43.
- A. Budhraja, I. Pels, and W. J. Waalewijn, Higher-point energy correlators: Factorization in the back-to-back limit & non-perturbative effects, J. High Energy Phys. 08 (2026) 154.
- P. Duan, W. Ke, G.-Y. Qin, and L. Wang, Uncover the correlation between jet energy correlators and multiplicity fluctuations, arXiv:2604.01102.
- J. Barata, M. V. Kuzmin, I. Moult, A. V. Sadofyev, and J. M. Silva, Hydrodynamics and energy correlators, arXiv:2604.21971.
- X.-N. Wang and Y. Zhu, Medium modification of -jets in high-energy heavy-ion collisions, Phys. Rev. Lett. 111, 062301 (2013).
- Y. He, T. Luo, X.-N. Wang, and Y. Zhu, Linear Boltzmann transport for jet propagation in the quark-gluon plasma: Elastic processes and medium recoil, Phys. Rev. C 91, 054908 (2015); 97, 019902(E) (2018).
- S. Cao, T. Luo, G.-Y. Qin, and X.-N. Wang, Linearized Boltzmann transport model for jet propagation in the quark-gluon plasma: Heavy quark evolution, Phys. Rev. C 94, 014909 (2016).
- S. Cao, T. Luo, G.-Y. Qin, and X.-N. Wang, Heavy and light flavor jet quenching at RHIC and LHC energies, Phys. Lett. B 777, 255 (2018).
- T. Luo, Y. He, S. Cao, and X.-N. Wang, Linear Boltzmann transport for jet propagation in the quark-gluon plasma: Inelastic processes and jet modification, Phys. Rev. C 109, 034919 (2024).
- W.-J. Xing, S. Cao, G.-Y. Qin, and H. Xing, Flavor hierarchy of jet quenching in relativistic heavy-ion collisions, Phys. Lett. B 805, 135424 (2020).
- L. Pang, Q. Wang, and X.-N. Wang, Effects of initial flow velocity fluctuation in event-by-event (3+1)D hydrodynamics, Phys. Rev. C 86, 024911 (2012).
- L.-G. Pang, Y. Hatta, X.-N. Wang, and B.-W. Xiao, Analytical and numerical Gubser solutions of the second-order hydrodynamics, Phys. Rev. D 91, 074027 (2015).
- L.-G. Pang, H. Petersen, and X.-N. Wang, Pseudorapidity distribution and decorrelation of anisotropic flow within the open-computing-language implementation CLVisc hydrodynamics, Phys. Rev. C 97, 064918 (2018).
- X.-Y. Wu, G.-Y. Qin, L.-G. Pang, and X.-N. Wang, (3+1)-D viscous hydrodynamics at finite net baryon density: Identified particle spectra, anisotropic flows, and flow fluctuations across energies relevant to the beam-energy scan at RHIC, Phys. Rev. C 105, 034909 (2022).
- W. Chen, S. Cao, T. Luo, L.-G. Pang, and X.-N. Wang, Effects of jet-induced medium excitation in -hadron correlation in A+A collisions, Phys. Lett. B 777, 86 (2018).
- W. Chen, S. Cao, T. Luo, L.-G. Pang, and X.-N. Wang, Medium modification of -jet fragmentation functions in Pb+Pb collisions at LHC, Phys. Lett. B 810, 135783 (2020).
- W. Zhao, W. Ke, W. Chen, T. Luo, and X.-N. Wang, From hydrodynamics to jet quenching, coalescence, and hadron cascade: A coupled approach to solving the puzzle, Phys. Rev. Lett. 128, 022302 (2022).
- T. Sjöstrand, S. Mrenna, and P. Z. Skands, A brief introduction to PYTHIA 8.1, Comput. Phys. Commun. 178, 852 (2008).
- T. Sjöstrand, S. Ask, J. R. Christiansen, R. Corke, N. Desai, P. Ilten, S. Mrenna, S. Prestel, C. O. Rasmussen, and P. Z. Skands, An introduction to PYTHIA 8.2, Comput. Phys. Commun. 191, 159 (2015).
- C. Bierlich et al., A comprehensive guide to the physics and usage of PYTHIA 8.3, SciPost Phys. Codebases 2022, 8 (2022).
- C. Andres, L. Apolinário, N. Armesto, A. Cordeiro, F. Dominguez, and J. G. Milhano, Assessing uncertainties in parton showers at double logarithmic accuracy for jet quenching studies, J. High Energy Phys. 08 (2025) 160.
- W. Ke and X.-N. Wang, QGP modification to single inclusive jets in a calibrated transport model, J. High Energy Phys. 05 (2021) 041.
- Y.-C. Dang, W.-J. Xing, S.-S. Cao, and G.-Y. Qin, An improved linear Boltzmann transport model for hadron and jet suppression in ultrarelativistic heavy-ion collisions, Nucl. Sci. Tech. 37, 210 (2026).
- M. Cacciari, G. P. Salam, and G. Soyez, FastJet user manual, Eur. Phys. J. C 72, 1896 (2012).
- D. Bertolini, T. Chan, and J. Thaler, Jet observables without jet algorithms, J. High Energy Phys. 04 (2014) 013.
- S. S. Gubser and A. Yarom, Universality of the diffusion wake in the gauge-string duality, Phys. Rev. D 77, 066007 (2008).
- B. Betz, J. Noronha, G. Torrieri, M. Gyulassy, I. Mishustin, and D. H. Rischke, Universality of the diffusion wake from stopped and punch-through jets in heavy-ion collisions, Phys. Rev. C 79, 034902 (2009).
- W. Chen, Z. Yang, Y. He, W. Ke, L. Pang, and X.-N. Wang, Search for the elusive jet-induced diffusion wake in -jets with 2D jet tomography in high-energy heavy-ion collisions, Phys. Rev. Lett. 127, 082301 (2021).
- Z. Yang, T. Luo, W. Chen, L.-G. Pang, and X.-N. Wang, 3D structure of jet-induced diffusion wake in an expanding quark-gluon plasma, Phys. Rev. Lett. 130, 052301 (2023).
- G. Aad et al. (ATLAS Collaboration), Search for the jet-induced diffusion wake in the quark-gluon plasma via measurements of jet-track correlations in photon-jet events in Pb + Pb collisions at with the ATLAS detector, Phys. Rev. C 111, 044909 (2025).
- V. Chekhovsky et al. (CMS Collaboration), Evidence of medium response to hard probes using correlations of Z bosons with hadrons in heavy ion collisions, Phys. Lett. B 874, 140120 (2026).
- Z. Yang and X.-N. Wang, Rapidity asymmetry of jet-hadron correlation as a robust signal of diffusion wake induced by dijets in high-energy heavy-ion collisions, Phys. Rev. Lett. 135, 072302 (2025).
- A. Hayrapetyan et al. (CMS Collaboration), Observation of the jet diffusion wake using dijets in heavy-ion collisions, Phys. Rev. Lett. 137, 071902 (2026).
- Z. Yang and X.-N. Wang, Diffusion wake: A distinctive consequence of the Mach-cone wake induced by supersonic jets in high-energy heavy-ion collisions, Research 8, 0941 (2025).
- Z. Yang and X.-N. Wang, Background-free signal of a jet-induced diffusion wake in quark-gluon plasma, Phys. Rev. C 113, L031901 (2026).
- J. Casalderrey-Solana, E. V. Shuryak, and D. Teaney, Conical flow induced by quenched QCD jets, J. Phys.: Conf. Ser. 27, 22 (2005).
- H. Stöcker, Collective flow signals the quark gluon plasma, Nucl. Phys. A 750, 121 (2005).
- J. Ruppert and B. Muller, Waking the colored plasma, Phys. Lett. B 618, 123 (2005).
- S. S. Gubser, S. S. Pufu, and A. Yarom, Sonic booms and diffusion wakes generated by a heavy quark in thermal AdS/CFT, Phys. Rev. Lett. 100, 012301 (2008).
- R. B. Neufeld, B. Muller, and J. Ruppert, Sonic Mach cones induced by fast partons in a perturbative quark-gluon plasma, Phys. Rev. C 78, 041901 (2008).
- G. Y. Qin, A. Majumder, H. Song, and U. Heinz, Energy and momentum deposited into a QCD medium by a jet shower, Phys. Rev. Lett. 103, 152303 (2009).
- H. Li, F. Liu, G.-l. Ma, X.-N. Wang, and Y. Zhu, Mach cone induced by -triggered jets in high-energy heavy-ion collisions, Phys. Rev. Lett. 106, 012301 (2011).
- I. Bouras, A. El, O. Fochler, H. Niemi, Z. Xu, and C. Greiner, Transition from ideal to viscous Mach cones in a kinetic transport approach, Phys. Lett. B 710, 641 (2012); Corrigendum to “Transition from ideal to viscous Mach cones in a kinetic transport approach” [Phys. Lett. B 710 (4–5) (2012) 641], 728, 156(E) (2014).
- A. Ayala, I. Dominguez, J. Jalilian-Marian, and M. E. Tejeda-Yeomans, Relating , and in an expanding quark-gluon plasma, Phys. Rev. C 94, 024913 (2016).
- L. Yan, S. Jeon, and C. Gale, Jet-medium interaction and conformal relativistic fluid dynamics, Phys. Rev. C 97, 034914 (2018).
- J. Casalderrey-Solana, J. G. Milhano, D. Pablos, K. Rajagopal, and X. Yao, Jet wake from linearized hydrodynamics, J. High Energy Phys. 05 (2021) 230.
- D. Pablos, Jet suppression from a small to intermediate to large radius, Phys. Rev. Lett. 124, 052301 (2020).