Measurement of substructure-dependent suppression of large-radius jets with charged particles in Pb+Pb collisions with ATLAS

ATLAS Collaboration; S. Alderweireldt; J.F. Allen; P. J.  Clark; J.R. Curran; D. Duda; S. M. Farrington; Y. Gao; J.M. Gargan; R.Y. González Andana; C. Jiang; C. Leonidopoulos; M. Firdaus M. Soberi; V. J.  Martin; L. Mijović; E.A. Pender; T. Qiu; J.M. Silva; A.L. Sopio; F. Ustuner; H. Watson; B.M. Wynne; Z. Xu

doi:10.1016/j.physletb.2025.139929

Measurement of substructure-dependent suppression of large-radius jets with charged particles in Pb+Pb collisions with ATLAS

ATLAS Collaboration
, S. Alderweireldt
, J.F. Allen
, P. J. Clark
, J.R. Curran
, D. Duda
, S. M. Farrington
, Y. Gao
, J.M. Gargan
, R.Y. González Andana
, C. Jiang
, C. Leonidopoulos
, M. Firdaus M. Soberi
, V. J. Martin
, L. Mijović
, E.A. Pender
, T. Qiu
, J.M. Silva
, A.L. Sopio
, F. Ustuner

H. Watson, B.M. Wynne, Z. Xu

School of Physics and Astronomy

Research output: Contribution to journal › Letter › peer-review

Abstract

Measurements of jet substructure in Pb+Pb collisions provide key insights into the mechanism of jet quenching in the hot and dense QCD medium created in these collisions.This Letter presents a measurement of the suppression of large-radius jets with a radius parameter of 𝑅 = 1.0 and its dependence on the jet substructure. The
measurement uses 1.72 nb−1 of Pb+Pb data and 255 pb−1 of 𝑝𝑝 data, both at √𝑠NN = 5.02 TeV, recorded with the ATLAS detector at the Large Hadron Collider. Large-radius jets are reconstructed by reclustering 𝑅 = 0.2 calorimetric jets and are measured for transverse momentum above 200 GeV. Jet substructure is evaluated using
charged-particle tracks, and the overall level of jet suppression is quantified using the jet nuclear modification factor (𝑅AA). The jet 𝑅AA is measured as a function of jet 𝑝T, the charged 𝑘𝑡 splitting scale (√𝑑12), and the angular separation (Δ𝑅12) of two leading sub-jets. The jet 𝑅AA gradually decreases with increasing √𝑑12, implying significantly stronger suppression of large-radius jets with larger 𝑘𝑡 splitting scale. The jet 𝑅AA gradually decreases for Δ𝑅12 in the range 0.01−0.2 and then remains consistent with a constant for Δ𝑅12 ≳ 0.2. The observed significant dependence of jet suppression on the jet substructure will provide new insights into its role in the quenching process.

Original language	English
Article number	139929
Pages (from-to)	1-17
Number of pages	17
Journal	Physics Letters B
Volume	871
DOIs	https://doi.org/10.1016/j.physletb.2025.139929
Publication status	Published - 1 Dec 2025

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3 Finished
3 Active

Experimental Particle Physics at the University of Edinburgh
Leonidopoulos, C. (Principal Investigator)
Science and Technology Facilities Council
1/04/23 → 30/09/26
Project: Research
Upgrade of the ATLAS detector at the LHC (2023-26)
Clark, P. (Principal Investigator)
Science and Technology Facilities Council
1/04/23 → 31/03/27
Project: Research
Experimental Particle Physics at the University of Edinburgh
Leonidopoulos, C. (Principal Investigator)
Science and Technology Facilities Council
1/10/22 → 30/09/26
Project: Research

Cite this

ATLAS Collaboration, Alderweireldt, S., Allen, J. F., Clark, P. J., Curran, J. R., Duda, D., Farrington, S. M., Gao, Y., Gargan, J. M., González Andana, R. Y., Jiang, C., Leonidopoulos, C., Soberi, M. F. M., Martin, V. J., Mijović, L., Pender, E. A., Qiu, T., Silva, J. M., Sopio, A. L., ... Xu, Z. (2025). Measurement of substructure-dependent suppression of large-radius jets with charged particles in Pb+Pb collisions with ATLAS. Physics Letters B, 871, 1-17. Article 139929. https://doi.org/10.1016/j.physletb.2025.139929

@article{492a19765bf344c0ae94e73b87e4176b,

title = "Measurement of substructure-dependent suppression of large-radius jets with charged particles in Pb+Pb collisions with ATLAS",

abstract = "Measurements of jet substructure in Pb+Pb collisions provide key insights into the mechanism of jet quenching in the hot and dense QCD medium created in these collisions.This Letter presents a measurement of the suppression of large-radius jets with a radius parameter of 𝑅 = 1.0 and its dependence on the jet substructure. The measurement uses 1.72 nb−1 of Pb+Pb data and 255 pb−1 of 𝑝𝑝 data, both at √𝑠NN = 5.02 TeV, recorded with the ATLAS detector at the Large Hadron Collider. Large-radius jets are reconstructed by reclustering 𝑅 = 0.2 calorimetric jets and are measured for transverse momentum above 200 GeV. Jet substructure is evaluated using charged-particle tracks, and the overall level of jet suppression is quantified using the jet nuclear modification factor (𝑅AA). The jet 𝑅AA is measured as a function of jet 𝑝T, the charged 𝑘𝑡 splitting scale (√𝑑12), and the angular separation (Δ𝑅12) of two leading sub-jets. The jet 𝑅AA gradually decreases with increasing √𝑑12, implying significantly stronger suppression of large-radius jets with larger 𝑘𝑡 splitting scale. The jet 𝑅AA gradually decreases for Δ𝑅12 in the range 0.01−0.2 and then remains consistent with a constant for Δ𝑅12 ≳ 0.2. The observed significant dependence of jet suppression on the jet substructure will provide new insights into its role in the quenching process.",

author = "\{ATLAS Collaboration\} and S. Alderweireldt and J.F. Allen and Clark, \{P. J.\} and J.R. Curran and D. Duda and Farrington, \{S. M.\} and Y. Gao and J.M. Gargan and \{Gonz{\'a}lez Andana\}, R.Y. and C. Jiang and C. Leonidopoulos and Soberi, \{M. Firdaus M.\} and Martin, \{V. J.\} and L. Mijovi{\'c} and E.A. Pender and T. Qiu and J.M. Silva and A.L. Sopio and F. Ustuner and H. Watson and B.M. Wynne and Z. Xu",

year = "2025",

month = dec,

day = "1",

doi = "10.1016/j.physletb.2025.139929",

language = "English",

volume = "871",

pages = "1--17",

journal = "Physics Letters B",

issn = "0370-2693",

publisher = "Elsevier",

}

ATLAS Collaboration, Alderweireldt, S, Allen, JF, Clark, PJ, Curran, JR, Duda, D , Farrington, SM , Gao, Y, Gargan, JM, González Andana, RY, Jiang, C, Leonidopoulos, C, Soberi, MFM, Martin, VJ , Mijović, L, Pender, EA, Qiu, T, Silva, JM, Sopio, AL, Ustuner, F, Watson, H , Wynne, BM & Xu, Z 2025, 'Measurement of substructure-dependent suppression of large-radius jets with charged particles in Pb+Pb collisions with ATLAS', Physics Letters B, vol. 871, 139929, pp. 1-17. https://doi.org/10.1016/j.physletb.2025.139929

TY - JOUR

T1 - Measurement of substructure-dependent suppression of large-radius jets with charged particles in Pb+Pb collisions with ATLAS

AU - ATLAS Collaboration

AU - Alderweireldt, S.

AU - Allen, J.F.

AU - Clark, P. J.

AU - Curran, J.R.

AU - Duda, D.

AU - Farrington, S. M.

AU - Gao, Y.

AU - Gargan, J.M.

AU - González Andana, R.Y.

AU - Jiang, C.

AU - Leonidopoulos, C.

AU - Soberi, M. Firdaus M.

AU - Martin, V. J.

AU - Mijović, L.

AU - Pender, E.A.

AU - Qiu, T.

AU - Silva, J.M.

AU - Sopio, A.L.

AU - Ustuner, F.

AU - Watson, H.

AU - Wynne, B.M.

AU - Xu, Z.

PY - 2025/12/1

Y1 - 2025/12/1

N2 - Measurements of jet substructure in Pb+Pb collisions provide key insights into the mechanism of jet quenching in the hot and dense QCD medium created in these collisions.This Letter presents a measurement of the suppression of large-radius jets with a radius parameter of 𝑅 = 1.0 and its dependence on the jet substructure. The measurement uses 1.72 nb−1 of Pb+Pb data and 255 pb−1 of 𝑝𝑝 data, both at √𝑠NN = 5.02 TeV, recorded with the ATLAS detector at the Large Hadron Collider. Large-radius jets are reconstructed by reclustering 𝑅 = 0.2 calorimetric jets and are measured for transverse momentum above 200 GeV. Jet substructure is evaluated using charged-particle tracks, and the overall level of jet suppression is quantified using the jet nuclear modification factor (𝑅AA). The jet 𝑅AA is measured as a function of jet 𝑝T, the charged 𝑘𝑡 splitting scale (√𝑑12), and the angular separation (Δ𝑅12) of two leading sub-jets. The jet 𝑅AA gradually decreases with increasing √𝑑12, implying significantly stronger suppression of large-radius jets with larger 𝑘𝑡 splitting scale. The jet 𝑅AA gradually decreases for Δ𝑅12 in the range 0.01−0.2 and then remains consistent with a constant for Δ𝑅12 ≳ 0.2. The observed significant dependence of jet suppression on the jet substructure will provide new insights into its role in the quenching process.

AB - Measurements of jet substructure in Pb+Pb collisions provide key insights into the mechanism of jet quenching in the hot and dense QCD medium created in these collisions.This Letter presents a measurement of the suppression of large-radius jets with a radius parameter of 𝑅 = 1.0 and its dependence on the jet substructure. The measurement uses 1.72 nb−1 of Pb+Pb data and 255 pb−1 of 𝑝𝑝 data, both at √𝑠NN = 5.02 TeV, recorded with the ATLAS detector at the Large Hadron Collider. Large-radius jets are reconstructed by reclustering 𝑅 = 0.2 calorimetric jets and are measured for transverse momentum above 200 GeV. Jet substructure is evaluated using charged-particle tracks, and the overall level of jet suppression is quantified using the jet nuclear modification factor (𝑅AA). The jet 𝑅AA is measured as a function of jet 𝑝T, the charged 𝑘𝑡 splitting scale (√𝑑12), and the angular separation (Δ𝑅12) of two leading sub-jets. The jet 𝑅AA gradually decreases with increasing √𝑑12, implying significantly stronger suppression of large-radius jets with larger 𝑘𝑡 splitting scale. The jet 𝑅AA gradually decreases for Δ𝑅12 in the range 0.01−0.2 and then remains consistent with a constant for Δ𝑅12 ≳ 0.2. The observed significant dependence of jet suppression on the jet substructure will provide new insights into its role in the quenching process.

U2 - 10.1016/j.physletb.2025.139929

DO - 10.1016/j.physletb.2025.139929

M3 - Letter

SN - 0370-2693

VL - 871

SP - 1

EP - 17

JO - Physics Letters B

JF - Physics Letters B

M1 - 139929

ER -

Measurement of substructure-dependent suppression of large-radius jets with charged particles in Pb+Pb collisions with ATLAS

Abstract

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Projects

Experimental Particle Physics at the University of Edinburgh

Upgrade of the ATLAS detector at the LHC (2023-26)

Experimental Particle Physics at the University of Edinburgh

Cite this