Journal Article

GSI-2026-00153

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Hard-photon-triggered jets in p − p and A − A collisions

Sirimanna, C. (Corresponding author) ; Tachibana, Y. ; Majumder, A. ; Angerami, A. ; Arora, R. ; Bass, S. A. ; Chen, Y. ; Datta, R. ; Du, L. ; Ehlers, R. ; Elfner, H.GSI* ; Fries, R. J. ; Gale, C. ; He, Y. ; Jacak, B. V. ; Jacobs, P. M. ; Jeon, S. ; Ji, Y. ; Jonas, F. ; Kasper, L. ; Kordell, M. ; Kumar, A. ; Kunnawalkam-Elayavalli, R. ; Latessa, J. ; Lee, Y.-J. ; Lemmon, R. ; Luzum, M. ; Mak, S. ; Mankolli, A. ; Martin, C. ; Mehryar, H. ; Mengel, T. ; Nattrass, C. ; Norman, J. ; Parker, C. ; Paquet, J.-F. ; Putschke, J. H. ; Roch, H. ; Roland, G. ; Schenke, B. ; Schwiebert, L. ; Sengupta, A. ; Shen, C. ; Singh, M. ; Soeder, D. ; Soltz, R. A. ; Soudi, I. ; Velkovska, J. ; Vujanovic, G. ; Wang, X.-N. ; Wu, X. ; Zhao, W.

2025
Inst. Woodbury, NY

Please use a persistent id in citations: doi:10.1103/yyr5-zp16  doi:10.15120/GSI-2026-00153

Report No.: arXiv:2412.19738

Abstract: An investigation of high-transverse-momentum (high-𝑝𝑇) photon-triggered jets in proton-proton (𝑝−𝑝) and ion-ion (𝐴−𝐴) collisions at √𝑠𝑁⁢𝑁=0.2 and 5.02TeV is carried out, using the multistage description of in-medium jet evolution. Monte Carlo simulations of hard scattering and energy loss in heavy-ion collisions are performed using parameters tuned in a previous study of the nuclear modification factor (𝑅𝐴⁢𝐴) for inclusive jets and high-𝑝𝑇hadrons. We obtain a good reproduction of the experimental data for photon-triggered jet 𝑅𝐴⁢𝐴, as measured by the ATLAS detector, the distribution of the ratio of jet to photon 𝑝𝑇 (𝑋𝐽⁢𝛾), measured by both CMS and ATLAS, and the photon-jet azimuthal correlation as measured by CMS. We obtain a moderate description of the photon-triggered jet 𝐼𝐴⁢𝐴, as measured by STAR. A noticeable improvement in the comparison is observed when one goes beyond prompt photons and includes bremsstrahlung and decay photons, revealing their significance in certain kinematic regions, particularly at 𝑋𝐽⁢𝛾>1. Moreover, azimuthal angle correlations demonstrate a notable impact of bremsstrahlung photons on the distribution, emphasizing their role in accurately describing experimental results. This work highlights the success of the multistage model of jet modification to straightforwardly predict (this set of) photon-triggered jet observables. This comparison, along with the role played by bremsstrahlung photons, has important consequences on the inclusion of such observables in a future Bayesian analysis.

Note: Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Funded by SCOAP3.

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Contributing Institute(s):

1. Heiße & Dichte QCD Materie (TES)

Research Program(s):

1. 612 - Cosmic Matter in the Laboratory (POF4-612) (POF4-612)

Experiment(s):

1. no experiment theory work (theory)

Appears in the scientific report 2025

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; ; ; Clarivate Analytics Master Journal List ; Current Contents - Electronics and Telecommunications Collection ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF < 5 ; JCR ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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