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Muhammad Ibrahim Abdulhamid, Bassam Aboona, Jaroslav Adam, Leszek Adamczyk, J. R. Adams, Ishu Aggarwal, Madan Mohan Aggarwal, Zubayer Ahammed, E. derson, D. M. Alpatov, Elke Caroline Aschenauer, Sameer Aslam, J. Atchison, Vipul Bairathi, W. Baker, Jonathan Gonzalo Ball Cap, Kenneth Barish, Rene Bellwied, Pratibha Bhagat, Anju Bhasin, Somadutta Bhatta, Jaroslav Bielčík, Jana Bielčíková, James D. Brandenburg, Xiang-Zhou Cai, Helen Louise Caines, Manuel Calderón de la Barca Sánchez, Daniel A. Cebra, Jakub Češka, Irakli Chakaberia, Petr Chaloupka, B. K. Chan, Z. Chang, A. Chatterjee, D. Chen, J. Chen, J. H. Chen, Z. Chen, J. Cheng, Y. Cheng, Subikash Choudhury, William Christie, X. Chu, Henry J. Crawford, Máté Csanád, G. Dale-Gau, A. Das, M. Daugherity, Ingo Martin Deppner, A. Dhamija, L. Di Carlo, Lidia Didenko, Prabhupada Dixit, X. Dong, James Lucus Drachenberg, Emilie Duckworth, James C. Dunlop, Jon M. Engelage, Geary Wareham Eppley, ShinIchi Esumi, Olga Y. Evdokimov, A. Ewigleben, Kjeld Oleg Eyser, Renee H. Fatemi, Salvatore Fazio, C. J. Feng, Yicheng Feng, Evan Finch, Yuri V. Fisyak, Fernando Antonio Flor, C. Fu, Carl A. Gagliardi, Tetyana Galatyuk, Frank Geurts, Navagyan Ghimire, Adam Gibson, Krishan Gopal, X. Gou, David P. Grosnick, Anik Gupta, Włodzimierz Guryn, Ahmed M. Hamed, Y. Han, Szymon Harabasz, Matthew D. Harasty, John W. Harris, Hannah Harrison-Smith, W. He, X. H. He, Y. He, Norbert Herrmann, Lukáš Holub, C. Hu, Q. Hu, Y. Hu, H. Huang, Huan Zhong Huang, Shengli Huang, T. Huang, X. Huang, Y. Huang, Y. Huang, Thomas J. Humanic, D. Isenhower, M. Isshiki, William W. Jacobs, Ashish Jalotra, Chitrasen Jena, Alexander Jentsch, Yuanjing Ji, Jiangyong Jia, C. Jin, X. Ju, Eleanor G. Judd, Sonia Kabana, M. L. Kabir, Skipper Kagamaster, Dmitry Kalinkin, K. Kang, David Kapukchyan, Declan Keane, Matthew Kelsey, Yevheniia V. Khyzhniak, Daniel P. Kikoła, B. Kimelman, D. Kincses, Ivan Kisel, A. Kiselev, Anders Garritt Knospe, H. S. Ko, Leszek Krzysztof Kosarzewski, L. Kramarik, Lokesh Kumar, Shyam Kumar, R. Kunnawalkam Elayavalli, Roy Alphanso Lacey, Jeffery M. Landgraf, Jerome Lauret, Alexei Lebedev, J. H. Lee, Y. H. Leung, N. Lewis, C. Li, W. Li, X. Li, Y. Li, Y. Li, Z. Li, X. Liang, Y. Liang, Robert Licenik, T. Lin, Michael A. Lisa, C. Liu, F. Liu, G. Liu, H. Liu, H. Liu, L. Liu, T. Liu, X. Liu, Y. Liu, Z. Liu, Tonko A. Ljubicic, William Joseph Llope, O. Lomicky, Ronald S. Longacre, E. M. Loyd, T. Lu, N. S. Lukow, X. F. Luo, L. Ma, R. Ma, Yu-Gang Ma, Niseem Magdy Abdelwahab Abdelrahman, Dukhishyam Mallick, Spyridon Margetis, Christina Markert, Howard S. Matis, Joel Anthony Mazer, Grant McNamara, K. Mi, Saskia Mioduszewski, Bedangadas Mohanty, Mriganka Mouli Mouli, Isaac A. Mooney, A. Mukherjee, M. I. Nagy, A. S. Nain, J. D. Nam, M. Nasim, D. Neff, John M. Nelson, Daniel B. Nemes, M. Nie, Grigory A. Nigmatkulov, Takafumi Niida, R. Nishitani, Toshihiro Nonaka, Grazyna Janina Odyniec, Akio Ogawa, Saehanseul Oh, K. Okubo, Brian S. Page, Robert Pak, Jinjin Pan, Ashish Pandav, Ashutosh Kumar Pandey, T. Pani, A. Paul, Bogdan Pawlik, Diana Pawłowska, Chris Perkins, Jan Marian Pluta, B. R. Pokhrel, Matthew Posik, Tristan Protzman, V. Prozorova, Navneet Kumar Pruthi, Mariusz Przybycien, Jörn H. Putschke, Z. Qin, H. Qiu, Amilkar Quintero, Cameron Racz, Sooraj Krishnan Radhakrishnan, N. Raha, Robert L. Ray, Rosi Jan Reed, Hans Georg Ritter, C. W. Robertson, Monika Robotkova, M. A. Rosales Aguilar, D. Roy, P. Roy Chowdhury, L. Ruan, A. K. Sahoo, Nihar Ranjan Sahoo, H. Sako, Sevil Salur, Susumu Sato, William B. Schmidke, Norbert Schmitz, F-J. Seck, Janet Elizabeth Seger, Richard Seto, Peter Seyboth, N. Shah, Prashanth V. Shanmuganathan, T. Shao, M. Sharma, Natasha Sharma, R. Sharma, S. R. Sharma, Ashik Ikbal Sheikh, D. Y. Shen, K. Shen, Shusu Shi, Y. Shi, Q. Y. Shou, F. Si, J. Singh, Subhash Singha, P. Sinha, Michael J. Skoby, Nikolai Smirnov, Yannick Söhngen, Y. Song, B. Srivastava, T. D. Shirvel Stanislaus, Maria Stefaniak, David J. Stewart, Blair Stringfellow, Y. Su, Alexandre Alarcon do Passo Suaide, Michal Šumbera, C. Sun, X. Sun, Y. Sun, Y. Sun, Bernd Surrow, Zachary W. Sweger, Paweł Szymański, A. Tamis, Aihong Tang, Z. Tang, Terence J. Tarnowsky, James H. Thomas, Anthony Robert Timmins, David Tlusty, Takahito Todoroki, C. A. Tomkiel, Stephen Trentalange, Robert E. Tribble, Prithwish Tribedy, Tomas Truhlar, Barbara Antonina Trzeciak, Oleg D. Tsai, C. Y. Tsang, Zhoudunming Tu, J. Tyler, Thomas Ullrich, David G. Underwood, Isaac Upsal, Gene Van Buren, Jan Vanek, Iouri Vassiliev, Veronica Verkest, Flemming Videbæk, Sergei Voloshin, F. Wang, G. Wang, J. S. Wang, X. Wang, Y. Wang, Y. Wang, Y. Wang, Z. Wang, Jason C. Webb, Philipp Weidenkaff, Gary D. Westfall, Daniel Wielanek, Howard Wieman, G. Wilks, Scott W. Wissink, Richard Witt, J. Wu, J. Wu, Xiao Wu, Y. Wu, B. Xi, Z. G. Xiao, Guannan Xie, W. Xie, H. Xu, N. Xu, Q. H. Xu, Y. Xu, Y. Xu, Z. Xu, Z. Xu, G. Yan, Z. Yan, C. Yang, Q. Yang, S. Yang, Y. Yang, Z. Ye, Z. Ye, L. Yi, K. Yip, Y. Yu, Hanna Paulina Zbroszczyk, W. Zha, C. Zhang, D. Zhang, J. Zhang, S. Zhang, W. Zhang, X. Zhang, Y. Zhang, Y. Zhang, Y. Zhang, Z. J. Zhang, Z. Zhang, Z. Zhang, F. Zhao, J. Zhao, M. Zhao, C. Zhou, J. Zhou, S. Zhou, Y. Zhou, X. Zhu, Maria Katarzyna Żurek, Maksym Zyzak

• In relativistic heavy-ion collisions, a global spin polarization, PH, of Λ and Λ¯ hyperons along the direction of the system angular momentum was discovered and measured across a broad range of collision energies and demonstrated a trend of increasing PH with decreasing sNN−−−√. A splitting between Λ and Λ¯ polarization may be possible due to their different magnetic moments in a late-stage magnetic field sustained by the quark-gluon plasma which is formed in the collision. The results presented in this study find no significant splitting at the collision energies of sNN−−−√=19.6 and 27 GeV in the RHIC Beam Energy Scan Phase II using the STAR detector, with an upper limit of PΛ¯−PΛ<0.24% and PΛ¯−PΛ<0.35%, respectively, at a 95% confidence level. We derive an upper limit on the naïve extraction of the late-stage magnetic field of B<9.4⋅1012 T and B<1.4⋅1013 T at sNN−−−√=19.6 and 27 GeV, respectively, although more thorough derivations are needed. Differential measurements of PH were performed with respect to collision centrality, transverse momentum, and rapidity. With our current acceptance of |y|<1 and uncertainties, we observe no dependence on transverse momentum and rapidity in this analysis. These results challenge multiple existing model calculations following a variety of different assumptions which have each predicted a strong dependence on rapidity in this collision-energy range.