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Measurement of Two-Point Energy Correlators within Jets in p+p Collisions at s=200  GeV

B. E. Aboona59, J. Adam17, G. Agakishiev33, I. Aggarwal45, M. M. Aggarwal45, Z. Ahammed66, A. Aitbayev33, I. Alekseev3,41, E. Alpatov41 et al. (STAR Collaboration)

E. Alpatov41, A. K. Alshammri34, A. Aparin33, S. Aslam22, J. Atchison2, G. S. Averichev33, V. Bairathi57, X. Bao53, K. Barish12, S. Behera28, P. Bhagat32, A. Bhasin32, S. Bhatta56, J. Bielcik17, J. Bielcikova17,19, I. G. Bordyuzhin3, J. D. Brandenburg44, A. V. Brandin41, C. Broodo25, X. Z. Cai54, H. Caines69, M. Calderón de la Barca Sánchez10, D. Cebra10, J. Ceska17, I. Chakaberia37, Y. S. Chang47, Z. Chang30, A. Chatterjee18, D. Chen12, J. H. Chen22, Q. Chen23, Z. Chen53, J. Cheng62, Y. Cheng11, W. Christie7, X. Chu7, S. Corey44, H. J. Crawford9, G. Dale-Gau14, A. Das17, T. G. Dedovich33, I. M. Deppner24, A. A. Derevschikov46, A. Deshpande56, A. Dhamija45, A. Dimri56, P. Dixit27, X. Dong37, J. L. Drachenberg2, E. Duckworth34, J. C. Dunlop7, J. Engelage9, G. Eppley48, S. Esumi63, O. Evdokimov14, O. Eyser7, R. Fatemi35, S. Fazio8, Y. Feng47, E. Finch55, Y. Fisyak7, F. A. Flor69, C. Fu31, T. Fu53, T. Gao53, F. Geurts48, A. Gibson65, K. Gopal28, X. Gou53, D. Grosnick65, A. Gu26, A. Gupta32, A. Hamed5, R. J. Hamilton69, X. Han44, M. D. Harasty10, J. W. Harris69, H. Harrison-Smith35, L. B. Havener69, X. H. He31, Y. He53, C. Hu64, Q. Hu31, Y. Hu37, H. Huang43,1, H. Z. Huang11, S. L. Huang56, T. Huang14, Y. Huang20, Y. Huang13, M. Isshiki63, W. W. Jacobs30, A. Jalotra32, C. Jena28, Y. Ji37, J. JJia56,7, C. Jin48, N. Jindal44, X. Ju50, E. G. Judd9, S. Kabana57, D. Kalinkin35, K. Kang62, D. Kapukchyan12, K. Kauder7, D. Keane34, A. Kechechyan33, M. Kesler34, A. Khanal67, J. Kim7, A. Kiselev7, A. G. Knospe38, L. Kochenda41, A. A. Korobitsin33, B. Korodi44, A. Yu. Kraeva41, P. Kravtsov41, L. Kumar45, M. C. Labonte10, R. Lacey56, J. M. Landgraf7, C. Larson35, A. Lebedev7, R. Lednicky33, J. H. Lee7, Y. H. Leung24, D. Li50, H-S. Li47, H. Li68, H. Li23, W. Li48, X. Li50, X. Li50, Y. Li62, Z. Li51, Z. Li50, X. Liang12, T. Lin53, Y. Lin23, C. Liu31, G. Liu51, H. Liu26, L. Liu13, Z. Liu13, T. Ljubicic48, O. Lomicky17, R. S. Longacre7, E. M. Loyd12, T. Lu31, J. Luo50, X. F. Luo13, V. B. Luong33, Ma22, R. Ma7, Y. G. Ma22, N. Magdy60, R. Manikandhan25, S. Margetis34, O. Matonoha17, O. Mezhanska17, K. Mi64, N. G. Minaev46, B. Mohanty42, B. Mondal42, M. M. Mondal42, I. Mooney69, D. A. Morozov46, M. I. Nagy20, C. J. Naim56, A. S. Nain45, J. D. Nam58, M. Nasim27, H. Nasrulloh50, E. Nedorezov33, J. M. Nelson9, M. Nie53, G. Nigmatkulov14, T. Niida63, L. V. Nogach46, T. Nonaka63, G. Odyniec37, A. Ogawa7, S. Oh52, V. A. Okorokov41, K. Okubo63, B. S. Page7, S. Pal17, A. Pandav37, A. Panday27, A. K. Pandey31, Y. Panebratsev33, T. Pani49, P. Parfenov41, A. Paul12, S. Paul56, C. Perkins9, B. R. Pokhrel58, I. D. Ponce Pinto69, M. Posik58, E. Pottebaum69, A. Povarov41, S. Prodhan28, T. L. Protzman38, N. K. Pruthi45, J. Putschke67, Z. Qin62, H. Qiu31, C. Racz12, S. K. Radhakrishnan34, A. Rana45, R. L. Ray61, C. W. Robertson47, O. V. Rogachevsky33, M. A. Rosales Aguilar35, D. Roy49, L. Ruan7, A. K. Sahoo27, N. R. Sahoo28, H. Sako63, S. Salur49, S. S. Sambyal32, E. Samigullin3, J. K. Sandhu38, S. Sato63, B. C. Schaefer38, N. Schmitz39, J. Seger16, R. Seto12, P. Seyboth39, N. Shah29, E. Shahaliev33, P. V. Shanmuganathan7, T. Shao22, M. Sharma32, N. Sharma27, R. Sharma28, S. R. Sharma28, A. I. Sheikh34, D. Shen53, D. Y. Shen31, K. Shen50, S. Shi13, Y. Shi53, F. Si50, J. Singh57, S. Singha31, P. Sinha28, M. J. Skoby6,47, Y. Söhngen24, Y. Song69, T. D. S. Stanislaus65, M. Strikhanov41, Y. Su50, X. Sun31, Y. Sun50, B. Surrow58, D. N. Svirida3, Z. W. Sweger10, A. C. Tamis69, A. H. Tang7, Z. Tang50, A. Taranenko41, T. Tarnowsky40, J. H. Thomas37, D. Tlusty16, M. V. Tokarev33, D. Torres Valladares48, S. Trentalange11, P. Tribedy7, B. Trzeciak17, O. D. Tsai11,7, C. Y. Tsang34,7, Z. Tu7, J. E. Tyler59, T. Ullrich7, D. G. Underwood4,65, G. Van Buren7, A. N. Vasiliev46,41, F. Videbæk7, S. Vokal33, S. A. Voloshin67, G. Wang11, J. S. Wang26, J. Wang53, K. Wang50, X. Wang53, Y. Wang50, Y. Wang13, Y. Wang62, Z. Wang53, J. C. Webb7, P. C. Weidenkaff24, G. D. Westfall40, H. Wieman37, G. Wilks14, S. W. Wissink30, C. P. Wong7, J. Wu64, X. Wu11, X. Wu50, B. Xi22, Z. G. Xiao62, G. Xie64, W. Xie47, H. Xu26, N. Xu13, Q. H. Xu53, Y. Xu53, Y. Xu13, Z. Xu34, Z. Xu4, G. Yan53, Z. Yan56, C. Yang53, Q. Yang53, S. Yang51, Y. Yang1,43, Z. Ye37, L. Yi53, Y. Yu53, W. Zha50, C. Zhang22, D. Zhang51, J. Zhang53, S. Zhang15, W. Zhang51, X. Zhang31, Y. Zhang31, Y. Zhang50, Y. Zhang53, Y. Zhang23, Z. Zhang7, Z. Zhang14, F. Zhao36, J. Zhao22, S. Zhou13, Y. Zhou13, X. Zhu62, M. Zurek4,7, and M. Zyzak21 (STAR Collaboration)

  • 1Academia Sinica, Nankang, 115
  • 2Abilene Christian University, Abilene, Texas 79699
  • 3Alikhanov Institute for Theoretical and Experimental Physics NRC “Kurchatov Institute”, Moscow 117218
  • 4Argonne National Laboratory, Argonne, Illinois 60439
  • 5American University in Cairo, New Cairo 11835, Egypt
  • 6Ball State University, Muncie, Indiana 47306
  • 7Brookhaven National Laboratory, Upton, New York 11973
  • 8University of Calabria & INFN-Cosenza, Rende 87036, Italy
  • 9University of California, Berkeley, California 94720
  • 10University of California, Davis, California 95616
  • 11University of California, Los Angeles, California 90095
  • 12University of California, Riverside, California 92521
  • 13Central China Normal University, Wuhan, Hubei 430079
  • 14University of Illinois at Chicago, Chicago, Illinois 60607
  • 15Chongqing University, Chongqing 401331
  • 16Creighton University, Omaha, Nebraska 68178
  • 17Czech Technical University in Prague, FNSPE, Prague 115 19, Czech Republic
  • 18National Institute of Technology Durgapur, Durgapur - 713209, India
  • 19Nuclear Physics Institute of the CAS, Rez 250 68, Czech Republic
  • 20ELTE Eötvös Loránd University, Budapest, Hungary H-1117
  • 21Frankfurt Institute for Advanced Studies FIAS, Frankfurt 60438, Germany
  • 22Fudan University, Shanghai 200433
  • 23Guangxi Normal University, Guilin 541004
  • 24University of Heidelberg, Heidelberg 69120, Germany
  • 25University of Houston, Houston, Texas 77204
  • 26Huzhou University, Huzhou, Zhejiang 313000
  • 27Indian Institute of Science Education and Research (IISER), Berhampur 760010, India
  • 28Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati 517507, India
  • 29Indian Institute Technology, Patna, Bihar 801106, India
  • 30Indiana University, Bloomington, Indiana 47408
  • 31Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, Gansu 730000
  • 32University of Jammu, Jammu 180001, India
  • 33Joint Institute for Nuclear Research, Dubna 141 980
  • 34Kent State University, Kent, Ohio 44242
  • 35University of Kentucky, Lexington, Kentucky 40506-0055
  • 36Lanzhou University, Lanzhou 730000
  • 37Lawrence Berkeley National Laboratory, Berkeley, California 94720
  • 38Lehigh University, Bethlehem, Pennsylvania 18015
  • 39Max-Planck-Institut für Physik, Munich 80805, Germany
  • 40Michigan State University, East Lansing, Michigan 48824
  • 41National Research Nuclear University MEPhI, Moscow 115409
  • 42National Institute of Science Education and Research, HBNI, Jatni 752050, India
  • 43National Cheng Kung University, Tainan 70101
  • 44The Ohio State University, Columbus, Ohio 43210
  • 45Panjab University, Chandigarh 160014, India
  • 46NRC “Kurchatov Institute,” Institute of High Energy Physics, Protvino 142281
  • 47Purdue University, West Lafayette, Indiana 47907
  • 48Rice University, Houston, Texas 77251
  • 49Rutgers University, Piscataway, New Jersey 08854
  • 50University of Science and Technology of China, Hefei, Anhui 230026
  • 51South China Normal University, Guangzhou, Guangdong 510631
  • 52Sejong University, Seoul 05006, South Korea
  • 53Shandong University, Qingdao, Shandong 266237
  • 54Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800
  • 55Southern Connecticut State University, New Haven, Connecticut 06515
  • 56State University of New York, Stony Brook, New York 11794
  • 57Instituto de Alta Investigación, Universidad de Tarapacá, Arica 1000000, Chile
  • 58Temple University, Philadelphia, Pennsylvania 19122
  • 59Texas A&M University, College Station, Texas 77843
  • 60Texas Southern University, Houston, Texas, 77004
  • 61University of Texas, Austin, Texas 78712
  • 62Tsinghua University, Beijing 100084
  • 63University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
  • 64University of Chinese Academy of Sciences, Beijing 101408
  • 65Valparaiso University, Valparaiso, Indiana 46383
  • 66Variable Energy Cyclotron Centre, Kolkata 700064, India
  • 67Wayne State University, Detroit, Michigan 48201
  • 68Wuhan University of Science and Technology, Wuhan, Hubei 430065
  • 69Yale University, New Haven, Connecticut 06520

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Phys. Rev. Lett. 135, 111901 – Published 10 September, 2025

DOI: https://doi.org/10.1103/wv2t-dkgn

Abstract

Hard-scattered partons ejected from high-energy proton-proton collisions undergo parton shower and hadronization, resulting in collimated collections of particles that are clustered into jets. A substructure observable that highlights the transition between the perturbative and nonperturbative regimes of jet evolution in terms of the angle between two particles is the two-point energy correlator (EEC). In this Letter, the first measurement of the EEC at RHIC is presented, using data taken from 200 GeV p+p collisions by the STAR experiment. The EEC is measured both for all the pairs of particles in jets and separately for pairs with like and opposite electric charges. These measurements demonstrate that the transition between perturbative and nonperturbative effects occurs within an angular region that is consistent with expectations of a universal hadronization regime that scales with jet momentum for a given initiator flavor. Additionally, a deviation from Monte Carlo predictions at small angles in the charge-selected sample could result from mechanics of hadronization not fully captured by current models.

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Phys. Rev. Lett. 135, 111901– Published 10 September, 2025
  • Received 4 March 2025
  • Revised 13 August 2025
  • Accepted 15 August 2025
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