- Letter
Global -hyperon polarization in collisions at
M. S. Abdallah5, B. E. Aboona55, J. Adam6, L. Adamczyk2, J. R. Adams39, J. K. Adkins30, G. Agakishiev28, I. Aggarwal41, M. M. Aggarwal41 et al. (STAR Collaboration)
M. M. Aggarwal41, Z. Ahammed60, I. Alekseev3,35, D. M. Anderson55, A. Aparin28, E. C. Aschenauer6, M. U. Ashraf11, F. G. Atetalla29, A. Attri41, G. S. Averichev28, V. Bairathi53, W. Baker10, J. G. Ball Cap20, K. Barish10, A. Behera52, R. Bellwied20, P. Bhagat27, A. Bhasin27, J. Bielcik14, J. Bielcikova38, I. G. Bordyuzhin3, J. D. Brandenburg6, A. V. Brandin35, I. Bunzarov28, J. Butterworth45, X. Z. Cai50, H. Caines63, M. Calderón de la Barca Sánchez8, D. Cebra8, I. Chakaberia31,6, P. Chaloupka14, B. K. Chan9, F.-H. Chang37, Z. Chang6, N. Chankova-Bunzarova28, A. Chatterjee11, S. Chattopadhyay60, D. Chen10, J. Chen49, J. H. Chen18, X. Chen48, Z. Chen49, J. Cheng57, M. Chevalier10, S. Choudhury18, W. Christie6, X. Chu6, H. J. Crawford7, M. Csanád16, M. Daugherity1, T. G. Dedovich28, I. M. Deppner19, A. A. Derevschikov43, A. Dhamija41, L. Di Carlo62, L. Didenko6, P. Dixit22, X. Dong31, J. L. Drachenberg1, E. Duckworth29, J. C. Dunlop6, N. Elsey62, J. Engelage7, G. Eppley45, S. Esumi58, O. Evdokimov12, A. Ewigleben32, O. Eyser6, R. Fatemi30, F. M. Fawzi5, S. Fazio6, P. Federic38, J. Fedorisin28, C. J. Feng37, Y. Feng44, P. Filip28, E. Finch51, Y. Fisyak6, A. Francisco63, C. Fu11, L. Fulek2, C. A. Gagliardi55, T. Galatyuk15, F. Geurts45, N. Ghimire54, A. Gibson59, K. Gopal23, X. Gou49, D. Grosnick59, A. Gupta27, W. Guryn6, A. I. Hamad29, A. Hamed5, Y. Han45, S. Harabasz15, M. D. Harasty8, J. W. Harris63, H. Harrison30, S. He11, W. He18, X. H. He26, Y. He49, S. Heppelmann8, S. Heppelmann42, N. Herrmann19, E. Hoffman20, L. Holub14, Y. Hu18, H. Huang37, H. Z. Huang9, S. L. Huang52, T. Huang37, X. Huang57, Y. Huang57, T. J. Humanic39, G. Igo9,*, D. Isenhower1, W. W. Jacobs25, C. Jena23, A. Jentsch6, Y. Ji31, J. Jia6,52, K. Jiang48, X. Ju48, E. G. Judd7, S. Kabana53, M. L. Kabir10, S. Kagamaster32, D. Kalinkin25,6, K. Kang57, D. Kapukchyan10, K. Kauder6, H. W. Ke6, D. Keane29, A. Kechechyan28, M. Kelsey62, Y. V. Khyzhniak35, D. P. Kikoła61, C. Kim10, B. Kimelman8, D. Kincses16, I. Kisel17, A. Kiselev6, A. G. Knospe32, H. S. Ko31, L. Kochenda35, L. K. Kosarzewski14, L. Kramarik14, P. Kravtsov35, L. Kumar41, S. Kumar26, R. Kunnawalkam Elayavalli63, J. H. Kwasizur25, R. Lacey52, S. Lan11, J. M. Landgraf6, J. Lauret6, A. Lebedev6, R. Lednicky28,38, J. H. Lee6, Y. H. Leung31, C. Li49, C. Li48, W. Li45, X. Li48, Y. Li57, X. Liang10, Y. Liang29, R. Licenik38, T. Lin49, Y. Lin11, M. A. Lisa39, F. Liu11, H. Liu25, H. Liu11, P. Liu52, T. Liu63, X. Liu39, Y. Liu55, Z. Liu48, T. Ljubicic6, W. J. Llope62, R. S. Longacre6, E. Loyd10, N. S. Lukow54, X. F. Luo11, L. Ma18, R. Ma6, Y. G. Ma18, N. Magdy12, D. Mallick36, S. Margetis29, C. Markert56, H. S. Matis31, J. A. Mazer46, N. G. Minaev43, S. Mioduszewski55, B. Mohanty36, M. M. Mondal52, I. Mooney62, D. A. Morozov43, A. Mukherjee16, M. Nagy16, J. D. Nam54, Md. Nasim22, K. Nayak11, D. Neff9, J. M. Nelson7, D. B. Nemes63, M. Nie49, G. Nigmatkulov35, T. Niida58, R. Nishitani58, L. V. Nogach43, T. Nonaka58, A. S. Nunes6, G. Odyniec31, A. Ogawa6, S. Oh31, V. A. Okorokov35, B. S. Page6, R. Pak6, J. Pan55, A. Pandav36, A. K. Pandey58, Y. Panebratsev28, P. Parfenov35, B. Pawlik40, D. Pawlowska61, H. Pei11, C. Perkins7, L. Pinsky20, R. L. Pintér16, J. Pluta61, B. R. Pokhrel54, G. Ponimatkin38, J. Porter31, M. Posik54, V. Prozorova14, N. K. Pruthi41, M. Przybycien2, J. Putschke62, H. Qiu26, A. Quintero54, C. Racz10, S. K. Radhakrishnan29, N. Raha62, R. L. Ray56, R. Reed32, H. G. Ritter31, M. Robotkova38, O. V. Rogachevskiy28, J. L. Romero8, D. Roy46, L. Ruan6, J. Rusnak38, N. R. Sahoo49, H. Sako58, S. Salur46, J. Sandweiss63,*, S. Sato58, W. B. Schmidke6, N. Schmitz33, B. R. Schweid52, F. Seck15, J. Seger13, M. Sergeeva9, R. Seto10, P. Seyboth33, N. Shah24, E. Shahaliev28, P. V. Shanmuganathan6, M. Shao48, T. Shao18, A. I. Sheikh29, D. Shen50, S. S. Shi11, Y. Shi49, Q. Y. Shou18, E. P. Sichtermann31, R. Sikora2, M. Simko38, J. Singh41, S. Singha26, M. J. Skoby44, N. Smirnov63, Y. Söhngen19, W. Solyst25, P. Sorensen6, H. M. Spinka4,*, B. Srivastava44, T. D. S. Stanislaus59, M. Stefaniak61, D. J. Stewart63, M. Strikhanov35, B. Stringfellow44, A. A. P. Suaide47, M. Sumbera38, B. Summa42, X. M. Sun11, X. Sun12, Y. Sun48, Y. Sun21, B. Surrow54, D. N. Svirida3, Z. W. Sweger8, P. Szymanski61, A. H. Tang6, Z. Tang48, A. Taranenko35, T. Tarnowsky34, J. H. Thomas31, A. R. Timmins20, D. Tlusty13, T. Todoroki58, M. Tokarev28, C. A. Tomkiel32, S. Trentalange9, R. E. Tribble55, P. Tribedy6, S. K. Tripathy16, T. Truhlar14, B. A. Trzeciak14, O. D. Tsai9, Z. Tu6, T. Ullrich6, D. G. Underwood4,59, I. Upsal49,6, G. Van Buren6, J. Vanek38, A. N. Vasiliev43, I. Vassiliev17, V. Verkest62, F. Videbæk6, S. Vokal28, S. A. Voloshin62, F. Wang44, G. Wang9, J. S. Wang21, P. Wang48, Y. Wang11, Y. Wang57, Z. Wang49, J. C. Webb6, P. C. Weidenkaff19, L. Wen9, G. D. Westfall34, H. Wieman31, S. W. Wissink25, J. Wu26, Y. Wu10, B. Xi50, Z. G. Xiao57, G. Xie31, W. Xie44, H. Xu21, N. Xu31, Q. H. Xu49, Y. Xu49, Z. Xu6, Z. Xu9, C. Yang49, Q. Yang49, S. Yang45, Y. Yang37, Z. Ye45, Z. Ye12, L. Yi49, K. Yip6, Y. Yu49, H. Zbroszczyk61, W. Zha48, C. Zhang52, D. Zhang11, J. Zhang49, S. Zhang12, S. Zhang18, X. P. Zhang57, Y. Zhang26, Y. Zhang48, Y. Zhang11, Z. J. Zhang37, Z. Zhang6, Z. Zhang12, J. Zhao44, C. Zhou18, X. Zhu57, M. Zurek4, and M. Zyzak17 (STAR Collaboration)
- 1Abilene Christian University, Abilene, Texas 79699
- 2AGH University of Science and Technology, FPACS, Cracow 30-059, Poland
- 3Alikhanov Institute for Theoretical and Experimental Physics NRC “Kurchatov Institute”, Moscow 117218, Russia
- 4Argonne National Laboratory, Argonne, Illinois 60439
- 5American University of Cairo, New Cairo 11835, New Cairo, Egypt
- 6Brookhaven National Laboratory, Upton, New York 11973
- 7University of California, Berkeley, California 94720
- 8University of California, Davis, California 95616
- 9University of California, Los Angeles, California 90095
- 10University of California, Riverside, California 92521
- 11Central China Normal University, Wuhan, Hubei 430079
- 12University of Illinois at Chicago, Chicago, Illinois 60607
- 13Creighton University, Omaha, Nebraska 68178
- 14Czech Technical University in Prague, FNSPE, Prague 115 19, Czech Republic
- 15Technische Universität Darmstadt, Darmstadt 64289, Germany
- 16ELTE Eötvös Loránd University, Budapest, Hungary H-1117
- 17Frankfurt Institute for Advanced Studies FIAS, Frankfurt 60438, Germany
- 18Fudan University, Shanghai, 200433
- 19University of Heidelberg, Heidelberg 69120, Germany
- 20University of Houston, Houston, Texas 77204
- 21Huzhou University, Huzhou, Zhejiang 313000
- 22Indian Institute of Science Education and Research (IISER), Berhampur 760010, India
- 23Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati 517507, India
- 24Indian Institute Technology, Patna, Bihar 801106, India
- 25Indiana University, Bloomington, Indiana 47408
- 26Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, Gansu 730000
- 27University of Jammu, Jammu 180001, India
- 28Joint Institute for Nuclear Research, Dubna 141 980, Russia
- 29Kent State University, Kent, Ohio 44242
- 30University of Kentucky, Lexington, Kentucky 40506-0055
- 31Lawrence Berkeley National Laboratory, Berkeley, California 94720
- 32Lehigh University, Bethlehem, Pennsylvania 18015
- 33Max-Planck-Institut für Physik, Munich 80805, Germany
- 34Michigan State University, East Lansing, Michigan 48824
- 35National Research Nuclear University MEPhI, Moscow 115409, Russia
- 36National Institute of Science Education and Research, HBNI, Jatni 752050, India
- 37National Cheng Kung University, Tainan 70101
- 38Nuclear Physics Institute of the CAS, Rez 250 68, Czech Republic
- 39Ohio State University, Columbus, Ohio 43210
- 40Institute of Nuclear Physics PAN, Cracow 31-342, Poland
- 41Panjab University, Chandigarh 160014, India
- 42Pennsylvania State University, University Park, Pennsylvania 16802
- 43NRC “Kurchatov Institute”, Institute of High Energy Physics, Protvino 142281, Russia
- 44Purdue University, West Lafayette, Indiana 47907
- 45Rice University, Houston, Texas 77251
- 46Rutgers University, Piscataway, New Jersey 08854
- 47Universidade de São Paulo, São Paulo, Brazil 05314-970
- 48University of Science and Technology of China, Hefei, Anhui 230026
- 49Shandong University, Qingdao, Shandong 266237
- 50Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800
- 51Southern Connecticut State University, New Haven, Connecticut 06515
- 52State University of New York, Stony Brook, New York 11794
- 53Instituto de Alta Investigación, Universidad de Tarapacá, Arica 1000000, Chile
- 54Temple University, Philadelphia, Pennsylvania 19122
- 55Texas A&M University, College Station, Texas 77843
- 56University of Texas, Austin, Texas 78712
- 57Tsinghua University, Beijing 100084
- 58University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
- 59Valparaiso University, Valparaiso, Indiana 46383
- 60Variable Energy Cyclotron Centre, Kolkata 700064, India
- 61Warsaw University of Technology, Warsaw 00-661, Poland
- 62Wayne State University, Detroit, Michigan 48201
- 63Yale University, New Haven, Connecticut 06520
- *Deceased.
Phys. Rev. C 104, L061901 – Published 21 December, 2021
DOI: https://doi.org/10.1103/PhysRevC.104.L061901
Abstract
Global hyperon polarization, , in collisions over a large range of collision energy, , was recently measured and successfully reproduced by hydrodynamic and transport models with intense fluid vorticity of the quark-gluon plasma. While naïve extrapolation of data trends suggests a large as the collision energy is reduced, the behavior of at small GeV is unknown. Operating the STAR experiment in fixed-target mode, we measured the polarization of hyperons along the direction of global angular momentum in collisions at GeV. The observation of substantial polarization of in these collisions may require a reexamination of the viscosity of any fluid created in the collision, of the thermalization timescale of rotational modes, and of hadronic mechanisms to produce global polarization.