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Energy Correlators within Jets in Transversely Polarized Proton-Proton Collisions at s=200  GeV

B. E. Aboona60, J. Adam18, G. Agakishiev33, I. Aggarwal46, M. M. Aggarwal46, Z. Ahammed67, E. C. Aschenauer8, A. Aitbayev33, I. Alekseev4,42 et al. (STAR Collaboration*)

I. Alekseev4,42, E. Alpatov42, A. K. Alshammri34, A. Aparin33, S. Aslam22, J. Atchison3, G. S. Averichev33, V. Bairathi58, X. Bao54, P. Barik27, K. Barish13, S. Behera28, P. Bhagat32, A. Bhasin32, S. Bhatta57, I. G. Bordyuzhin4, J. D. Brandenburg45, A. V. Brandin42, C. Broodo25, X. Z. Cai55, H. Caines71, M. Calderón de la Barca Sánchez11, D. Cebra11, J. Ceska18, I. Chakaberia37, Y. S. Chang48, Z. Chang30, A. Chatterjee19, D. Chen13, J. H. Chen22, L. Chen14, Q. Chen23, W. Chen22, Z. Chen54, J. Cheng63, Y. Cheng12, W. Christie8, X. Chu8, S. Corey45, H. J. Crawford10, G. Dale-Gau18, A. Das18, D. De Souza Lemos8, T. G. Dedovich33, I. M. Deppner24, A. A. Derevschikov47, A. Deshpande57, A. Dhamija46, A. Dimri57, P. Dixit22, X. Dong37, J. L. Drachenberg3, E. Duckworth34, J. C. Dunlop8, Y. S. El-Feky6, J. Engelage10, G. Eppley49, S. Esumi64, O. Evdokimov15, O. Eyser8, B. Fan14, Y. Fang63, R. Fatemi35, S. Fazio9, H. Feng14, Y. Feng14, E. Finch56, Y. Fisyak8, F. A. Flor5, B. Fu14, C. Fu31, T. Fu54, T. Gao54, Gao22, G. Garcia8, F. Geurts49, A. Gibson66, A. Giri25, K. Gopal28, X. Gou54, D. Grosnick66, A. Gu26, J. Gu22, A. Gupta32, A. Hamed6, R. J. Hamilton71, J. Han14, X. Han45, M. D. Harasty11, J. W. Harris71, H. Harrison-Smith35, L. B. Havener71, X. H. He31, Y. He54, C. Hu65, Q. Hu31, Y. Hu37, H. Huang44,1, H. Z. Huang12, S. L. Huang57, T. Huang1, Y. Huang20, Y. Huang31, Y. Huang22, M. Isshiki64, W. W. Jacobs30, A. Jalotra32, C. Jena28, Y. Ji65, J. Jia57,8, X. Jiang14, C. Jin49, Y. Jin14, N. Jindal45, X. Ju51, E. G. Judd10, S. Kabana58, D. Kalinkin35, J. Kang53, K. Kang63, A. R. Kanuganti8, D. Kapukchyan13, K. Kauder8, D. Keane34, A. Kechechyan33, M. Kesler34, A. Khanal69, A. Khanal59, J. Kim8, A. Kiselev8, A. G. Knospe38, L. Kochenda42, Y. Kong14, A. A. Korobitsin33, B. Korodi45, A. Yu. Kraeva42, P. Kravtsov42, L. Kumar46, M. C. Labonte11, R. Lacey57, J. M. Landgraf8, C. Larson35, R. Lednicky33, J. H. Lee8, Y. H. Leung24, C. Li14, D. Li51, H-S. Li48, H. Li70, H. Li23, H. Li14, W. Li49, X. Li51, X. Li51, Y. Li63, Z. Li52, Z. Li51, X. Liang13, T. Lin54, Y. Lin23, C. Liu31, G. Liu52, H. Liu26, L. Liu54, L. Liu22, Z. Liu22, Z. Liu14, T. Ljubicic49, LNU34, O. Lomicky18, E. M. Loyd13, T. Lu31, J. Luo51, X. F. Luo14, V. B. Luong33, L. Ma22, R. Ma8, Y. G. Ma22, N. Magdy61, R. Manikandhan25, O. Matonoha18, Mccallips66, K. Menduli27, K. Mi65, N. G. Minaev47, B. Mohanty43, B. Mondal43, M. M. Mondal39, I. Mooney71, D. A. Morozov47, M. I. Nagy20, C. J. Naim57, A. S. Nain46, J. D. Nam59, M. Nasim27, H. Nasrulloh51, K. Nayak2, E. Nedorezov33, J. M. Nelson10, M. Nie54, G. Nigmatkulov15, T. Niida64, L. V. Nogach47, T. Nonaka64, G. Odyniec37, A. Ogawa8, S. Oh53, V. A. Okorokov42, K. Okubo64, B. S. Page8, M. Pal59, S. Pal18, A. Pandav37, A. Panday27, A. K. Pandey68, Y. Panebratsev33, T. Pani50, P. Parfenov42, A. Paul13, S. Paul57, C. Perkins10, S. Ping22, I. D. Ponce Pinto71, M. Posik59, E. Pottebaum71, A. Povarov42, Praharaj27, S. Prodhan28, T. L. Protzman38, N. K. Pruthi46, J. Putschke69, Y. Qi14, Z. Qin63, H. Qiu31, S. K. Radhakrishnan34, A. Rana46, R. L. Ray62, C. W. Robertson48, O. V. Rogachevsky33, M. A. Rosales Aguilar35, D. Roy50, L. Ruan8, A. K. Sahoo31, N. R. Sahoo28, H. Sako64, S. Salur50, S. S. Sambyal32, E. Samigullin4, D. T. Samuel34, J. K. Sandhu38, S. Sato64, B. C. Schaefer38, J. Seger17, R. Seto13, P. Seyboth40, N. Shah29, E. Shahaliev33, P. V. Shanmuganathan8, T. Shao22, M. Sharma32, R. Sharma28, S. R. Sharma28, A. I. Sheikh34, D. Shen54, D. Y. Shen31, K. Shen51, S. Shi14, Y. Shi54, E. Shulga8, F. Si51, J. Singh58, S. Singha31, P. Sinha28, M. J. Skoby7,48, Y. Söhngen24, Y. Song71, T. D. S. Stanislaus66, M. Strikhanov42, Y. Su51, X. Sun31, Y. Sun51, B. Surrow59, D. N. Svirida4, Z. W. Sweger11, A. C. Tamis71, A. H. Tang8, Z. Tang51, Tanner66, A. Taranenko42, T. Tarnowsky41, J. H. Thomas37, A. Timofeev33, D. Tlusty17, M. V. Tokarev33, D. Torres-Valladares49, S. Trentalange12, O. D. Tsai12,8, C. Y. Tsang5,8, Z. Tu8, J. E. Tyler60, T. Ullrich8, D. G. Underwood5,66, G. Van Buren8, A. N. Vasiliev47,42, F. Videbæk8, S. Vokal33, S. A. Voloshin69, F. Wang48, G. Wang12, G. Wang14, J. S. Wang26, J. Wang54, K. Wang51, X. Wang54, Y. Wang51, Y. Wang14, Y. Wang63, Z. Wang22, Z. Wang14, J. C. Webb8, P. C. Weidenkaff24, G. D. Westfall41, H. Wieman37, G. Wilks15, S. W. Wissink30, C. P. Wong8, J. Wu65, Wu22, X. Wu12, X. Wu51, X. Wu14, B. Xi22, Y. Xiao22, Z. G. Xiao63, G. Xie65, W. Xie48, H. Xu26, N. Xu14, Q. H. Xu54, X. Xu63, Y. Xu54, Y. Xu22, Y. Xu14, Y. Xu31, Z. Xu34, Z. Xu5, G. Yan54, Z. Yan57, C. Yang54, Q. Yang54, S. Yang52, Y. Yang1,44, Z. Ye52, Z. Ye37, L. Yi54, Y. Yu54, W. Yuan63, W. Zha51, C. Zhang22, D. Zhang52, J. Zhang54, K. Zhang14, L. Zhang14, S. Zhang16, W. Zhang52, X. Zhang31, Y. Zhang31, Y. Zhang51, Y. Zhang54, Y. Zhang23, Z. Zhang8, Z. Zhang15, F. Zhao36, J. Zhao22, Zhao22, S. Zhou14, Y. Zhou14, C. Zhu14, X. Zhu63, and M. Zyzak21 (STAR Collaboration*)

  • 1Academia Sinica, Nankang, 115
  • 2Panchayat College (PC), Bargarh, Affiliated with Sambalpur University (SU), Odisha 768028, India
  • 3Abilene Christian University, Abilene, Texas 79699
  • 4Alikhanov Institute for Theoretical and Experimental Physics NRC “Kurchatov Institute,” Moscow 117218
  • 5Argonne National Laboratory, Argonne, Illinois 60439
  • 6American University in Cairo, New Cairo 11835, Egypt
  • 7Ball State University, Muncie, Indiana 47306
  • 8Brookhaven National Laboratory, Upton, New York 11973
  • 9University of Calabria and INFN-Cosenza, Rende 87036, Italy
  • 10University of California, Berkeley, California 94720
  • 11University of California, Davis, California 95616
  • 12University of California, Los Angeles, California 90095
  • 13University of California, Riverside, California 92521
  • 14Central China Normal University, Wuhan, Hubei 430079
  • 15University of Illinois at Chicago, Chicago, Illinois 60607
  • 16Chongqing University, Chongqing, 401331
  • 17Creighton University, Omaha, Nebraska 68178
  • 18Czech Technical University in Prague, FNSPE, Prague 115 19, Czech Republic
  • 19National Institute of Technology Durgapur, Durgapur—713209, India
  • 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
  • 39Lovely Professional University, Jalandhar—Delhi G.T. Road, Pagwara, Punjab, 144411, India
  • 40Max-Planck-Institut für Physik, Munich 80805, Germany
  • 41Michigan State University, East Lansing, Michigan 48824
  • 42National Research Nuclear University MEPhI, Moscow 115409
  • 43National Institute of Science Education and Research, HBNI, Jatni 752050, India
  • 44National Cheng Kung University, Tainan 70101
  • 45The Ohio State University, Columbus, Ohio 43210
  • 46Panjab University, Chandigarh 160014, India
  • 47NRC “Kurchatov Institute,” Institute of High Energy Physics, Protvino 142281
  • 48Purdue University, West Lafayette, Indiana 47907
  • 49Rice University, Houston, Texas 77251
  • 50Rutgers University, Piscataway, New Jersey 08854
  • 51University of Science and Technology of China, Hefei, Anhui 230026
  • 52South China Normal University, Guangzhou, Guangdong 510631
  • 53Sejong University, Seoul, 05006, Republic of Korea
  • 54Shandong University, Qingdao, Shandong 266237
  • 55Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800
  • 56Southern Connecticut State University, New Haven, Connecticut 06515
  • 57State University of New York, Stony Brook, New York 11794
  • 58Instituto de Alta Investigación, Universidad de Tarapacá, Arica 1000000, Chile
  • 59Temple University, Philadelphia, Pennsylvania 19122
  • 60Texas A&M University, College Station, Texas 77843
  • 61Texas Southern University, Houston, Texas 77004
  • 62University of Texas, Austin, Texas 78712
  • 63Tsinghua University, Beijing 100084
  • 64University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
  • 65University of Chinese Academy of Sciences, Beijing, 101408
  • 66Valparaiso University, Valparaiso, Indiana 46383
  • 67Variable Energy Cyclotron Centre, Kolkata 700064, India
  • 68Warsaw University of Technology, Warsaw 00-661, Poland
  • 69Wayne State University, Detroit, Michigan 48201
  • 70Wuhan University of Science and Technology, Wuhan, Hubei 430065
  • 71Yale University, New Haven, Connecticut 06520

  • *Contact author: star-publication@bnl.gov

Phys. Rev. Lett. 137, 111902 – Published 8 September, 2026

DOI: https://doi.org/10.1103/fgsf-gx2q

Abstract

We report the first measurement of one- and two-point energy correlators within jets in transversely polarized proton-proton collisions at s=200  GeV, using the STAR detector at the Relativistic Heavy Ion Collider. These observables quantify the energy-weighted angular distribution of single hadrons and hadron pairs within jets, respectively. Sizable spin-dependent asymmetries are observed for π+, π−, and π+π− pairs, revealing the onset of nonperturbative dynamics at specific angular scales. By projecting the fragmentation dynamics onto Mellin moments, these measurements provide sensitivity to the nucleon’s transversity while minimizing uncertainties from nonperturbative fragmentation functions. These results establish energy correlators as a novel and precise probe of nucleon structure and open a promising avenue for three-dimensional nucleon tomography at the future Electron-Ion Collider.

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References (36)

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