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arxiv: 2510.19571 · v2 · submitted 2025-10-22 · ✦ hep-ex

Evidence of transverse polarization of Xi⁰ hyperon in psi(3686)rightarrowXi⁰bar{Xi}⁰

BESIII Collaboration: M. Ablikim , M. N. Achasov , P. Adlarson , X. C. Ai , R. Aliberti , A. Amoroso , Q. An , Y. Bai
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O. Bakina Y. Ban H.-R. Bao V. Batozskaya K. Begzsuren N. Berger M. Berlowski M. B. Bertani D. Bettoni F. Bianchi E. Bianco A. Bortone I. Boyko R. A. Briere A. Brueggemann H. Cai M. H. Cai X. Cai A. Calcaterra G. F. Cao N. Cao S. A. Cetin X. Y. Chai J. F. Chang T. T. Chang G. R. Che Y. Z. Che C. H. Chen Chao Chen G. Chen H. S. Chen H. Y. Chen M. L. Chen S. J. Chen S. M. Chen T. Chen X. R. Chen X. T. Chen X. Y. Chen Y. B. Chen Y. Q. Chen Z. K. Chen J. C. Cheng L. N. Cheng S. K. Choi X. Chu G. Cibinetto F. Cossio J. Cottee-Meldrum H. L. Dai J. P. Dai X. C. Dai A. Dbeyssi R. E. de Boer D. Dedovich C. Q. Deng Z. Y. Deng A. Denig I. Denisenko M. Destefanis F. De Mori X. X. Ding Y. Ding Y. X. Ding J. Dong L. Y. Dong M. Y. Dong X. Dong M. C. Du S. X. Du X. L. Du Y. Y. Duan Z. H. Duan P. Egorov G. F. Fan J. J. Fan Y. H. Fan J. Fang S. S. Fang W. X. Fang Y. Q. Fang L. Fava F. Feldbauer G. Felici C. Q. Feng J. H. Feng L. Feng Q. X. Feng Y. T. Feng M. Fritsch C. D. Fu J. L. Fu Y. W. Fu H. Gao Y. Gao Y. N. Gao Y. Y. Gao Z. Gao S. Garbolino I. Garzia L. Ge P. T. Ge Z. W. Ge C. Geng E. M. Gersabeck A. Gilman K. Goetzen J. D. Gong L. Gong W. X. Gong W. Gradl S. Gramigna M. Greco M. D. Gu M. H. Gu C. Y. Guan A. Q. Guo J. N. Guo L. B. Guo M. J. Guo R. P. Guo X. Guo Y. P. Guo A. Guskov J. Gutierrez T. T. Han F. Hanisch K. D. Hao X. Q. Hao F. A. Harris C. Z. He K. L. He F. H. Heinsius C. H. Heinz Y. K. Heng C. Herold P. C. Hong G. Y. Hou X. T. Hou Y. R. Hou Z. L. Hou H. M. Hu J. F. Hu Q. P. Hu S. L. Hu T. Hu Y. Hu Z. M. Hu G. S. Huang K. X. Huang L. Q. Huang P. Huang X. T. Huang Y. P. Huang Y. S. Huang T. Hussain N. H\"usken N. in der Wiesche J. Jackson Q. Ji Q. P. Ji W. Ji X. B. Ji X. L. Ji X. Q. Jia Z. K. Jia D. Jiang H. B. Jiang P. C. Jiang S. J. Jiang X. S. Jiang Y. Jiang J. B. Jiao J. K. Jiao Z. Jiao S. Jin Y. Jin M. Q. Jing X. M. Jing T. Johansson S. Kabana N. Kalantar-Nayestanaki X. L. Kang X. S. Kang M. Kavatsyuk B. C. Ke V. Khachatryan A. Khoukaz O. B. Kolcu B. Kopf L. Kr\"oger M. Kuessner X. Kui N. Kumar A. Kupsc W. K\"uhn Q. Lan W. N. Lan T. T. Lei M. Lellmann T. Lenz C. Li C. H. Li C. K. Li D. M. Li F. Li G. Li H. B. Li H. J. Li H. L. Li H. N. Li Hui Li J. R. Li J. S. Li J. W. Li K. Li K. L. Li L. J. Li Lei Li M. H. Li M. R. Li P. L. Li P. R. Li Q. M. Li Q. X. Li R. Li S. X. Li Shanshan Li T. Li T. Y. Li W. D. Li W. G. Li X. Li X. H. Li X. K. Li X. L. Li X. Y. Li X. Z. Li Y. Li Y. G. Li Y. P. Li Z. H. Li Z. J. Li Z. X. Li Z. Y. Li C. Liang H. Liang Y. F. Liang Y. T. Liang G. R. Liao L. B. Liao M. H. Liao Y. P. Liao J. Libby A. Limphirat D. X. Lin L. Q. Lin T. Lin B. J. Liu B. X. Liu C. X. Liu F. Liu F. H. Liu Feng Liu G. M. Liu H. Liu H. B. Liu H. M. Liu Huihui Liu J. B. Liu J. J. Liu K. Liu K. Y. Liu Ke Liu L. Liu L. C. Liu Lu Liu M. H. Liu P. L. Liu Q. Liu S. B. Liu W. M. Liu W. T. Liu X. Liu X. K. Liu X. L. Liu X. Y. Liu Y. Liu Y. B. Liu Z. A. Liu Z. D. Liu Z. Q. Liu Z. Y. Liu X. C. Lou H. J. Lu J. G. Lu X. L. Lu Y. Lu Y. H. Lu Y. P. Lu Z. H. Lu C. L. Luo J. R. Luo J. S. Luo M. X. Luo T. Luo X. L. Luo Z. Y. Lv X. R. Lyu Y. F. Lyu Y. H. Lyu F. C. Ma H. L. Ma Heng Ma J. L. Ma L. L. Ma L. R. Ma Q. M. Ma R. Q. Ma R. Y. Ma T. Ma X. T. Ma X. Y. Ma Y. M. Ma F. E. Maas I. Mackay M. Maggiora S. Malde Q. A. Malik H. X. Mao Y. J. Mao Z. P. Mao S. Marcello A. Marshall F. M. Melendi Y. H. Meng Z. X. Meng G. Mezzadri H. Miao T. J. Min R. E. Mitchell X. H. Mo B. Moses N. Yu. Muchnoi J. Muskalla Y. Nefedov F. Nerling H. Neuwirth Z. Ning S. Nisar Q. L. Niu W. D. Niu Y. Niu C. Normand S. L. Olsen Q. Ouyang S. Pacetti X. Pan Y. Pan A. Pathak Y. P. Pei M. Pelizaeus H. P. Peng X. J. Peng Y. Y. Peng K. Peters K. Petridis J. L. Ping R. G. Ping S. Plura V. Prasad F. Z. Qi H. R. Qi M. Qi S. Qian W. B. Qian C. F. Qiao J. H. Qiao J. J. Qin J. L. Qin L. Q. Qin L. Y. Qin P. B. Qin X. P. Qin X. S. Qin Z. H. Qin J. F. Qiu Z. H. Qu J. Rademacker C. F. Redmer A. Rivetti M. Rolo G. Rong S. S. Rong F. Rosini Ch. Rosner M. Q. Ruan N. Salone A. Sarantsev Y. Schelhaas K. Schoenning M. Scodeggio W. Shan X. Y. Shan Z. J. Shang J. F. Shangguan L. G. Shao M. Shao C. P. Shen H. F. Shen W. H. Shen X. Y. Shen B. A. Shi H. Shi J. L. Shi J. Y. Shi S. Y. Shi X. Shi H. L. Song J. J. Song M. H. Song T. Z. Song W. M. Song Y. X. Song Zirong Song S. Sosio S. Spataro S Stansilaus F. Stieler S. S Su G. B. Sun G. X. Sun H. Sun H. K. Sun J. F. Sun K. Sun L. Sun R. Sun S. S. Sun T. Sun W. Y. Sun Y. C. Sun Y. H. Sun Y. J. Sun Y. Z. Sun Z. Q. Sun Z. T. Sun C. J. Tang G. Y. Tang J. Tang J. J. Tang L. F. Tang Y. A. Tang L. Y. Tao M. Tat J. X. Teng J. Y. Tian W. H. Tian Y. Tian Z. F. Tian I. Uman B. Wang Bo Wang C. Wang Cong Wang D. Y. Wang H. J. Wang J. Wang J. J. Wang J. P. Wang K. Wang L. L. Wang L. W. Wang M. Wang N. Y. Wang S. Wang Shun Wang T. Wang T. J. Wang W. Wang W. P. Wang X. Wang X. F. Wang X. L. Wang X. N. Wang Xin Wang Y. Wang Y. D. Wang Y. F. Wang Y. H. Wang Y. J. Wang Y. L. Wang Y. N. Wang Yaqian Wang Yi Wang Yuan Wang Z. Wang Z. L. Wang Z. Q. Wang Z. Y. Wang Ziyi Wang D. Wei D. H. Wei H. R. Wei F. Weidner S. P. Wen U. Wiedner G. Wilkinson M. Wolke J. F. Wu L. H. Wu L. J. Wu Lianjie Wu S. G. Wu S. M. Wu X. Wu Y. J. Wu Z. Wu L. Xia B. H. Xiang D. Xiao G. Y. Xiao H. Xiao Y. L. Xiao Z. J. Xiao C. Xie K. J. Xie Y. Xie Y. G. Xie Y. H. Xie Z. P. Xie T. Y. Xing C. J. Xu G. F. Xu H. Y. Xu M. Xu Q. J. Xu Q. N. Xu T. D. Xu X. P. Xu Y. Xu Y. C. Xu Z. S. Xu F. Yan L. Yan W. B. Yan W. C. Yan W. H. Yan W. P. Yan X. Q. Yan H. J. Yang H. L. Yang H. X. Yang J. H. Yang R. J. Yang Y. Yang Y. H. Yang Y. Q. Yang Y. Z. Yang Z. P. Yao M. Ye M. H. Ye Z. J. Ye Junhao Yin Z. Y. You B. X. Yu C. X. Yu G. Yu J. S. Yu L. W. Yu T. Yu X. D. Yu Y. C. Yu C. Z. Yuan H. Yuan J. Yuan L. Yuan M. K. Yuan S. H. Yuan Y. Yuan C. X. Yue Ying Yue A. A. Zafar F. R. Zeng S. H. Zeng X. Zeng Yujie Zeng Y. J. Zeng Y. C. Zhai Y. H. Zhan Shunan Zhang B. L. Zhang B. X. Zhang D. H. Zhang G. Y. Zhang H. Zhang H. C. Zhang H. H. Zhang H. Q. Zhang H. R. Zhang H. Y. Zhang J. Zhang J. J. Zhang J. L. Zhang J. Q. Zhang J. S. Zhang J. W. Zhang J. X. Zhang J. Y. Zhang J. Z. Zhang Jianyu Zhang L. M. Zhang Lei Zhang N. Zhang P. Zhang Q. Zhang Q. Y. Zhang R. Y. Zhang S. H. Zhang Shulei Zhang X. M. Zhang X. Y. Zhang Y. Zhang Y. T. Zhang Y. H. Zhang Y. P. Zhang Z. D. Zhang Z. H. Zhang Z. L. Zhang Z. X. Zhang Z. Y. Zhang Z. Z. Zhang Zh. Zh. Zhang G. Zhao J. Y. Zhao J. Z. Zhao L. Zhao M. G. Zhao S. J. Zhao Y. B. Zhao Y. L. Zhao Y. X. Zhao Z. G. Zhao A. Zhemchugov B. Zheng B. M. Zheng J. P. Zheng W. J. Zheng X. R. Zheng Y. H. Zheng B. Zhong C. Zhong H. Zhou J. Q. Zhou S. Zhou X. Zhou X. K. Zhou X. R. Zhou X. Y. Zhou Y. X. Zhou Y. Z. Zhou A. N. Zhu J. Zhu K. Zhu K. J. Zhu K. S. Zhu L. Zhu L. X. Zhu S. H. Zhu T. J. Zhu W. D. Zhu W. J. Zhu W. Z. Zhu Y. C. Zhu Z. A. Zhu X. Y. Zhuang J. H. Zou J. Zu
This is my paper

Pith reviewed 2026-05-18 04:45 UTC · model grok-4.3

classification ✦ hep-ex
keywords transverse polarizationhyperoncharmonium decaybranching fractionCP observablesangular distributionweak decay parametersS-wave D-wave contributions
0
0 comments X

The pith

The decay ψ(3686) to Ξ⁰ Ξ⁰bar shows evidence for transverse polarization of the Ξ⁰ hyperon at 4.4 sigma significance.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper sets out to establish evidence for transverse polarization in the Ξ⁰ hyperon from the decay of ψ(3686) into a hyperon and antihyperon pair. A reader would care because polarization measurements probe the spin alignment mechanisms in strong decays of charmonium to baryons. The work also supplies more precise values for the decay branching fraction and the relative S-wave versus D-wave strengths. It further determines the weak decay parameters of the hyperon and tests two CP observables, both found consistent with conservation.

Core claim

The central claim is the observation of transverse polarization for the Ξ⁰ hyperon with 4.4 sigma significance in ψ(3686) to Ξ⁰ Ξ⁰bar, together with improved measurements of the branching fraction, the S-to-D wave ratio, the angular distribution parameter, and the weak decay parameters, while the CP observables A^Ξ⁰_CP and Δφ^Ξ⁰_CP remain consistent with zero.

What carries the argument

Angular distribution fit to the decay chain after corrections for acceptance and efficiency, used to isolate the transverse polarization component and related parameters.

If this is right

  • The observed polarization indicates a preferred spin orientation in the production of the hyperon pair.
  • The updated branching fraction and wave ratio refine the description of the strong decay amplitude.
  • More precise weak decay parameters allow tighter comparison with theoretical models of hyperon decays.
  • The CP observables being consistent with zero at the present level supports the absence of large CP violation in this channel.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The result may help discriminate between different models of baryon pair production in vector charmonium decays.
  • Similar polarization studies in other charmonium-to-baryon channels could reveal systematic patterns.
  • With larger future datasets the same framework could set stronger limits on CP-violating phases.

Load-bearing premise

The angular parametrization in the fit correctly isolates the transverse polarization once detector acceptance, efficiency, and backgrounds have been accounted for.

What would settle it

A new measurement of the same decay with similar or higher statistics that finds a polarization significance below three sigma would refute the reported evidence.

Figures

Figures reproduced from arXiv: 2510.19571 by A. Amoroso, A. A. Zafar, A. Bortone, A. Brueggemann, A. Calcaterra, A. Dbeyssi, A. Denig, A. Gilman, A. Guskov, A. Khoukaz, A. Kupsc, A. Limphirat, A. Marshall, A. N. Zhu, A. Pathak, A. Q. Guo, A. Rivetti, A. Sarantsev, A. Zhemchugov, B. A. Shi, B. C. Ke, BESIII Collaboration: M. Ablikim, B. H. Xiang, B. J. Liu, B. Kopf, B. L. Zhang, B. Moses, B. M. Zheng, Bo Wang, B. Wang, B. X. Liu, B. X. Yu, B. X. Zhang, B. Zheng, B. Zhong, C. D. Fu, C. F. Qiao, C. F. Redmer, C. Geng, Chao Chen, C. H. Chen, C. Herold, C. H. Heinz, C. H. Li, Ch. Rosner, C. J. Tang, C. J. Xu, C. K. Li, C. Li, C. Liang, C. L. Luo, C. Normand, Cong Wang, C. P. Shen, C. Q. Deng, C. Q. Feng, C. Wang, C. Xie, C. X. Liu, C. X. Yu, C. X. Yue, C. Y. Guan, C. Z. He, C. Zhong, C. Z. Yuan, D. Bettoni, D. Dedovich, D. H. Wei, D. H. Zhang, D. Jiang, D. M. Li, D. Wei, D. Xiao, D. X. Lin, D. Y. Wang, E. Bianco, E. M. Gersabeck, F. A. Harris, F. Bianchi, F. C. Ma, F. Cossio, F. De Mori, F. E. Maas, Feng Liu, F. Feldbauer, F. Hanisch, F. H. Heinsius, F. H. Liu, F. Li, F. Liu, F. M. Melendi, F. Nerling, F. Rosini, F. R. Zeng, F. Stieler, F. Weidner, F. Yan, F. Z. Qi, G. B. Sun, G. Chen, G. Cibinetto, G. F. Cao, G. Felici, G. F. Fan, G. F. Xu, G. Li, G. Mezzadri, G. M. Liu, G. R. Che, G. R. Liao, G. Rong, G. S. Huang, G. Wilkinson, G. X. Sun, G. Y. Hou, G. Y. Tang, G. Yu, G. Y. Xiao, G. Y. Zhang, G. Zhao, H. B. Jiang, H. B. Li, H. B. Liu, H. Cai, H. C. Zhang, Heng Ma, H. F. Shen, H. Gao, H. H. Zhang, H. J. Li, H. J. Lu, H. J. Wang, H. J. Yang, H. K. Sun, H. L. Dai, H. Liang, H. Liu, H. L. Li, H. L. Ma, H. L. Song, H. L. Yang, H. M. Hu, H. Miao, H. M. Liu, H. Neuwirth, H. N. Li, H. P. Peng, H. Q. Zhang, H.-R. Bao, H. R. Qi, H. R. Wei, H. R. Zhang, H. S. Chen, H. Shi, H. Sun, Huihui Liu, Hui Li, H. Xiao, H. X. Mao, H. X. Yang, H. Y. Chen, H. Yuan, H. Y. Xu, H. Y. Zhang, H. Zhang, H. Zhou, I. Boyko, I. Denisenko, I. Garzia, I. Mackay, I. Uman, J. B. Jiao, J. B. Liu, J. C. Cheng, J. Cottee-Meldrum, J. D. Gong, J. Dong, J. Fang, J. F. Chang, J. F. Hu, J. F. Qiu, J. F. Shangguan, J. F. Sun, J. F. Wu, J. G. Lu, J. Gutierrez, J. H. Feng, J. H. Qiao, J. H. Yang, J. H. Zou, Jianyu Zhang, J. Jackson, J. J. Fan, J. J. Liu, J. J. Qin, J. J. Song, J. J. Tang, J. J. Wang, J. J. Zhang, J. K. Jiao, J. L. Fu, J. Libby, J. L. Ma, J. L. Ping, J. L. Qin, J. L. Shi, J. L. Zhang, J. Muskalla, J. N. Guo, J. P. Dai, J. P. Wang, J. P. Zheng, J. Q. Zhang, J. Q. Zhou, J. Rademacker, J. R. Li, J. R. Luo, J. S. Li, J. S. Luo, J. S. Yu, J. S. Zhang, J. Tang, Junhao Yin, J. Wang, J. W. Li, J. W. Zhang, J. X. Teng, J. X. Zhang, J. Y. Shi, J. Y. Tian, J. Yuan, J. Y. Zhang, J. Y. Zhao, J. Zhang, J. Zhu, J. Zu, J. Z. Zhang, J. Z. Zhao, K. Begzsuren, K. D. Hao, Ke Liu, K. Goetzen, K. J. Xie, K. J. Zhu, K. L. He, K. Li, K. Liu, K. L. Li, K. Peters, K. Petridis, K. Schoenning, K. Sun, K. S. Zhu, K. Wang, K. X. Huang, K. Y. Liu, K. Zhu, L. B. Guo, L. B. Liao, L. C. Liu, Lei Li, Lei Zhang, L. Fava, L. Feng, L. F. Tang, L. Ge, L. Gong, L. G. Shao, L. H. Wu, Lianjie Wu, L. J. Li, L. J. Wu, L. Kr\"oger, L. Liu, L. L. Ma, L. L. Wang, L. M. Zhang, L. N. Cheng, L. Q. Huang, L. Q. Lin, L. Q. Qin, L. R. Ma, L. Sun, Lu Liu, L. W. Wang, L. W. Yu, L. Xia, L. X. Zhu, L. Yan, L. Y. Dong, L. Y. Qin, L. Y. Tao, L. Yuan, L. Zhao, L. Zhu, M. B. Bertani, M. Berlowski, M. C. Du, M. Destefanis, M. D. Gu, M. Fritsch, M. Greco, M. G. Zhao, M. H. Cai, M. H. Gu, M. H. Li, M. H. Liao, M. H. Liu, M. H. Song, M. H. Ye, M. J. Guo, M. Kavatsyuk, M. Kuessner, M. K. Yuan, M. L. Chen, M. Lellmann, M. Maggiora, M. N. Achasov, M. Pelizaeus, M. Qi, M. Q. Jing, M. Q. Ruan, M. R. Li, M. Rolo, M. Scodeggio, M. Shao, M. Tat, M. Wang, M. Wolke, M. X. Luo, M. Xu, M. Y. Dong, M. Ye, N. Berger, N. Cao, N. H\"usken, N. in der Wiesche, N. Kalantar-Nayestanaki, N. Kumar, N. Salone, N. Yu. Muchnoi, N. Y. Wang, N. Zhang, O. Bakina, O. B. Kolcu, P. Adlarson, P. B. Qin, P. C. Hong, P. C. Jiang, P. Egorov, P. Huang, P. L. Li, P. L. Liu, P. R. Li, P. T. Ge, P. Zhang, Q. A. Malik, Q. An, Q. Ji, Q. J. Xu, Q. Lan, Q. Liu, Q. L. Niu, Q. M. Li, Q. M. Ma, Q. N. Xu, Q. Ouyang, Q. P. Hu, Q. P. Ji, Q. X. Feng, Q. X. Li, Q. Y. Zhang, Q. Zhang, R. A. Briere, R. Aliberti, R. E. de Boer, R. E. Mitchell, R. G. Ping, R. J. Yang, R. Li, R. P. Guo, R. Q. Ma, R. Sun, R. Y. Ma, R. Y. Zhang, S. A. Cetin, S. B. Liu, S. Garbolino, S. Gramigna, S. G. Wu, Shanshan Li, Shulei Zhang, Shunan Zhang, Shun Wang, S. H. Yuan, S. H. Zeng, S. H. Zhang, S. H. Zhu, S. J. Chen, S. Jin, S. J. Jiang, S. J. Zhao, S. Kabana, S. K. Choi, S. L. Hu, S. L. Olsen, S. Malde, S. Marcello, S. M. Chen, S. M. Wu, S. Nisar, S. Pacetti, S. Plura, S. P. Wen, S. Qian, S. S. Fang, S. Sosio, S. Spataro, S. S. Rong, S. S Su, S. S. Sun, S Stansilaus, S. Wang, S. X. Du, S. X. Li, S. Y. Shi, S. Zhou, T. Chen, T. D. Xu, T. Hu, T. Hussain, T. J. Min, T. Johansson, T. J. Wang, T. J. Zhu, T. Lenz, T. Li, T. Lin, T. Luo, T. Ma, T. Sun, T. T. Chang, T. T. Han, T. T. Lei, T. Wang, T. Y. Li, T. Yu, T. Y. Xing, T. Z. Song, U. Wiedner, V. Batozskaya, V. Khachatryan, V. Prasad, W. B. Qian, W. B. Yan, W. C. Yan, W. D. Li, W. D. Niu, W. D. Zhu, W. G. Li, W. Gradl, W. H. Shen, W. H. Tian, W. H. Yan, W. Ji, W. J. Zheng, W. J. Zhu, W. K\"uhn, W. M. Liu, W. M. Song, W. N. Lan, W. P. Wang, W. P. Yan, W. Shan, W. T. Liu, W. Wang, W. X. Fang, W. X. Gong, W. Y. Sun, W. Z. Zhu, X. B. Ji, X. Cai, X. C. Ai, X. C. Dai, X. Chu, X. C. Lou, X. Dong, X. D. Yu, X. F. Wang, X. Guo, X. H. Li, X. H. Mo, Xin Wang, X. J. Peng, X. K. Li, X. K. Liu, X. Kui, X. K. Zhou, X. L. Du, X. Li, X. Liu, X. L. Ji, X. L. Kang, X. L. Li, X. L. Liu, X. L. Lu, X. L. Luo, X. L. Wang, X. M. Jing, X. M. Zhang, X. N. Wang, X. Pan, X. P. Qin, X. P. Xu, X. Q. Hao, X. Q. Jia, X. Q. Yan, X. R. Chen, X. R. Lyu, X. R. Zheng, X. R. Zhou, X. Shi, X. S. Jiang, X. S. Kang, X. S. Qin, X. T. Chen, X. T. Hou, X. T. Huang, X. T. Ma, X. Wang, X. Wu, X. X. Ding, X. Y. Chai, X. Y. Chen, X. Y. Li, X. Y. Liu, X. Y. Ma, X. Y. Shan, X. Y. Shen, X. Y. Zhang, X. Y. Zhou, X. Y. Zhuang, X. Zeng, X. Zhou, X. Z. Li, Yaqian Wang, Y. A. Tang, Y. Bai, Y. Ban, Y. B. Chen, Y. B. Liu, Y. B. Zhao, Y. C. Sun, Y. C. Xu, Y. C. Yu, Y. C. Zhai, Y. C. Zhu, Y. Ding, Y. D. Wang, Y. F. Liang, Y. F. Lyu, Y. F. Wang, Y. Gao, Y. G. Li, Y. G. Xie, Y. H. Fan, Y. H. Lu, Y. H. Lyu, Y. H. Meng, Y. H. Sun, Y. Hu, Y. H. Wang, Y. H. Xie, Y. H. Yang, Y. H. Zhan, Y. H. Zhang, Y. H. Zheng, Ying Yue, Yi Wang, Y. Jiang, Y. Jin, Y. J. Mao, Y. J. Sun, Y. J. Wang, Y. J. Wu, Y. J. Zeng, Y. K. Heng, Y. Li, Y. Liu, Y. Lu, Y. L. Wang, Y. L. Xiao, Y. L. Zhao, Y. M. Ma, Y. Nefedov, Y. N. Gao, Y. Niu, Y. N. Wang, Y. Pan, Y. P. Guo, Y. P. Huang, Y. P. Li, Y. P. Liao, Y. P. Lu, Y. P. Pei, Y. P. Zhang, Y. Q. Chen, Y. Q. Fang, Y. Q. Yang, Y. R. Hou, Y. Schelhaas, Y. S. Huang, Y. T. Feng, Y. Tian, Y. T. Liang, Y. T. Zhang, Yuan Wang, Yujie Zeng, Y. Wang, Y. W. Fu, Y. X. Ding, Y. Xie, Y. X. Song, Y. Xu, Y. X. Zhao, Y. X. Zhou, Y. Yang, Y. Y. Duan, Y. Y. Gao, Y. Y. Peng, Y. Yuan, Y. Z. Che, Y. Zhang, Y. Z. Sun, Y. Z. Yang, Y. Z. Zhou, Z. A. Liu, Z. A. Zhu, Z. D. Liu, Z. D. Zhang, Z. F. Tian, Z. Gao, Z. G. Zhao, Z. H. Duan, Z. H. Li, Z. H. Lu, Z. H. Qin, Z. H. Qu, Z. H. Zhang, Zh. Zh. Zhang, Zirong Song, Ziyi Wang, Z. Jiao, Z. J. Li, Z. J. Shang, Z. J. Xiao, Z. J. Ye, Z. K. Chen, Z. K. Jia, Z. L. Hou, Z. L. Wang, Z. L. Zhang, Z. M. Hu, Z. Ning, Z. P. Mao, Z. P. Xie, Z. P. Yao, Z. Q. Liu, Z. Q. Sun, Z. Q. Wang, Z. S. Xu, Z. T. Sun, Z. Wang, Z. W. Ge, Z. Wu, Z. X. Li, Z. X. Meng, Z. X. Zhang, Z. Y. Deng, Z. Y. Li, Z. Y. Liu, Z. Y. Lv, Z. Y. Wang, Z. Y. You, Z. Y. Zhang, Z. Z. Zhang.

Figure 1
Figure 1. Figure 1: FIG. 1. Definition of the coordinate system used to describe the [PITH_FULL_IMAGE:figures/full_fig_p001_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2. Distribution of [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: shows the resulting polarization parameter Py and spin correlations together with the fit results with respect to cos θΞ0 in 10 intervals, where the first and last intervals are ignored due to extremely low statistics. Table I summarizes the numerical results in the fit. The relative phase ∆Φ for ψ(3686) → Ξ 0Ξ¯0 decay differs from zero with a signifi￾cance of larger than 4.4σ. Other parameters are measure… view at source ↗
read the original abstract

Using $(2.712\pm0.014)\times10^{9}$ $\psi(3686)$ events collected with the BESIII detector at the BEPCII collider, we report an evidence of $\Xi^{0}$ transverse polarization with a significance of 4.4$\sigma$, a precise measurement of the branching fraction and the ratios between the $S$-wave and $D$-wave contributions of $\psi(3686)\to\Xi^{0}\bar\Xi^{0}$. The weak decay parameters ($\phi_{\Xi^0/\bar{\Xi}^{0}}$, $\alpha_{\Xi^0/\bar{\Xi}^{0}}$) and the angular distribution ($\alpha_{\psi}$) are also measured with higher precision compared to the previous measurements. Furthermore, two the $CP$ observables are also determined to be $A^{\Xi^0}_{CP} = -0.014 \pm 0.030 \pm 0.010$ and $\Delta\phi^{\Xi^0}_{CP} = 0.000 \pm 0.028 \pm 0.003$~rad, which are still consistent with $CP$ conservation at 1$\sigma$ level under the current statistics.

Editorial analysis

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Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 2 minor

Summary. The manuscript analyzes (2.712 ± 0.014) × 10^9 ψ(3686) events collected with the BESIII detector and reports evidence for transverse polarization of the Ξ⁰ hyperon in ψ(3686) → Ξ⁰ Ξ⁰-bar at 4.4σ significance. It also presents precise measurements of the branching fraction, S/D-wave ratios, weak-decay parameters φ_Ξ⁰/Ξ⁰-bar and α_Ξ⁰/Ξ⁰-bar, the production angular parameter α_ψ, and CP observables A^Ξ⁰_CP = −0.014 ± 0.030 ± 0.010 and Δφ^Ξ⁰_CP = 0.000 ± 0.028 ± 0.003 rad, the latter two consistent with CP conservation.

Significance. If the central result holds, the 4.4σ evidence for transverse Ξ⁰ polarization in this charmonium decay provides a new experimental handle on baryon production mechanisms in e⁺e⁻ collisions near the ψ(3686) resonance. The large data set yields improved precision on α_ψ and the weak-decay parameters relative to earlier measurements, and the CP observables add useful constraints on CP violation in the hyperon sector. The multi-dimensional angular analysis is a standard and appropriate method for this measurement.

major comments (1)
  1. [Angular distribution analysis] The 4.4σ significance for transverse polarization is extracted from a multi-dimensional angular fit that must correctly isolate the polarization term after folding in detector acceptance, efficiency, and background. The manuscript should provide explicit validation (e.g., fit stability under varied efficiency parametrizations or residual-background studies) in the angular-analysis section to confirm that no unmodeled correlation biases the polarization parameter or its significance.
minor comments (2)
  1. [Abstract and results] The abstract states improved precision on α_ψ and weak-decay parameters but does not quantify the improvement relative to previous results; a brief comparison table or statement in the results section would help readers assess the advance.
  2. [CP observables] Notation for the CP observables (A^Ξ⁰_CP and Δφ^Ξ⁰_CP) is introduced without an explicit definition of how they are constructed from the measured parameters; a short equation or reference in the text would clarify this.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the careful review and constructive comment on our manuscript. We agree that explicit validation of the multi-dimensional angular fit is important to confirm the robustness of the transverse polarization measurement. We have incorporated additional studies addressing this point in the revised version.

read point-by-point responses

  1. Referee: [Angular distribution analysis] The 4.4σ significance for transverse polarization is extracted from a multi-dimensional angular fit that must correctly isolate the polarization term after folding in detector acceptance, efficiency, and background. The manuscript should provide explicit validation (e.g., fit stability under varied efficiency parametrizations or residual-background studies) in the angular-analysis section to confirm that no unmodeled correlation biases the polarization parameter or its significance.

    Authors: We thank the referee for highlighting this important aspect. In the revised manuscript, we have added a new subsection in the angular-analysis section (Section 4.3) that presents explicit validation studies. These include: (i) repeating the fit with alternative efficiency parametrizations derived from different Monte Carlo samples and binning schemes, and (ii) varying the residual-background modeling by changing the sideband subtraction and background shape assumptions. The transverse polarization parameter and its significance remain stable (always above 4σ) under these variations, with no evidence of bias from unmodeled correlations. Corresponding figures and tables documenting the results of these checks have been included. revision: yes

Circularity Check

0 steps flagged

Direct experimental measurement; no derivation reduces to inputs by construction

full rationale

The paper is a collider data analysis reporting a 4.4σ significance for transverse polarization of Ξ⁰ extracted via multi-dimensional angular fits to ψ(3686) → Ξ⁰Ξ⁰-bar events, with corrections for detector acceptance, efficiency, and background. The central result is a statistical fit to observed distributions, not a first-principles derivation or prediction. No equations or sections show self-definitional relations, fitted parameters renamed as predictions, or load-bearing self-citations that close the logic loop. External comparisons to prior measurements and consistency checks with CP observables provide independent benchmarks. The analysis chain remains self-contained against data without circular reduction.

Axiom & Free-Parameter Ledger

2 free parameters · 1 axioms · 0 invented entities

This experimental measurement relies on standard particle-physics assumptions such as conservation of angular momentum and the validity of the angular distribution parametrization for polarization extraction; no new entities or ad-hoc parameters are introduced beyond the usual fit parameters for branching fraction and amplitudes.

free parameters (2)
  • transverse polarization parameter
    Fitted from angular distributions to quantify the observed polarization signal.
  • S/D-wave ratio
    Ratio of partial-wave amplitudes in the production decay, extracted from data.
axioms (1)
  • standard math Standard assumptions of angular momentum conservation and parity in electromagnetic and strong decays of charmonium.
    Invoked implicitly when parametrizing the angular distribution of the decay products.

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Works this paper leans on

54 extracted references · 54 canonical work pages

  1. [1]

    Gonzalez and J

    E. Gonzalez and J. I. Illana, CERN-PPE-94-33

    work page

  2. [2]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D93, 072003 (2016)

    work page 2016

  3. [3]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D95, 052003 (2017)

    work page 2017

  4. [4]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Lett. B770, 217 (2017)

    work page 2017

  5. [5]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. Lett.125. 052004 (2020)

    work page 2020

  6. [6]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. Lett.131, 191802 (2023)

    work page 2023

  7. [7]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. Lett.133, 101902 (2024)

    work page 2024

  8. [8]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D108, L011101 (2023)

    work page 2023

  9. [9]

    Ablikimet al.(BESIII Collaboration), Nature Phys.15, 631 (2019)

    M. Ablikimet al.(BESIII Collaboration), Nature Phys.15, 631 (2019)

    work page 2019

  10. [10]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D105, L011101 (2022)

    work page 2022

  11. [11]

    Ablikimet al.(BESIII Collaboration), Nature606, 64 (2022)

    M. Ablikimet al.(BESIII Collaboration), Nature606, 64 (2022)

    work page 2022

  12. [12]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. Lett.129. 131801 (2022)

    work page 2022

  13. [13]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D106, L091101 (2022)

    work page 2022

  14. [14]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D108, L031106 (2023)

    work page 2023

  15. [15]

    Ablikimet al.(BESIII Collaboration), JHEP10, 081 (2023) [erratum: JHEP12, 080 (2023)]

    M. Ablikimet al.(BESIII Collaboration), JHEP10, 081 (2023) [erratum: JHEP12, 080 (2023)]

    work page 2023

  16. [16]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. Lett.132, 101801 (2024)

    work page 2024

  17. [17]

    Ablikimet al.(BESIII Collaboration), JHEP12, 186 (2024)

    M. Ablikimet al.(BESIII Collaboration), JHEP12, 186 (2024)

    work page 2024

  18. [18]

    Alekseev, A

    M. Alekseev, A. Amoroso, R. B. Ferroli, I. Balossino, M. Bertani, D. Bettoni, F. Bianchi, J. Chai, G. Cibinetto and F. Cossio,et al.Chin. Phys. C43, 023103 (2019)

    work page 2019

  19. [19]

    R. B. Ferroli, A. Mangoni, S. Pacetti and K. Zhu, Phys. Rev. D 103, 016005 (2021)

    work page 2021

  20. [20]

    S. M. Wu, J. J. Wu and B. S. Zou, Phys. Rev. D104, 054018 (2021)

    work page 2021

  21. [21]

    A. D. Sakharov, Pis’ma Zh. Eksp. Teor. Fiz.5, 32 (1967)

    work page 1967

  22. [22]

    H. Liu, J. Zhang and X. Wang, Symmetry15, 214 (2023)

    work page 2023

  23. [23]

    J. H. Christenson, J. W. Cronin, V . L. Fitch, and R. Turlay, Phys. Rev. Lett.13, 138 (1964)

    work page 1964

  24. [24]

    Aubertet al.(BABARCollaboration), Phys

    B. Aubertet al.(BABARCollaboration), Phys. Rev. Lett87, 091801 (2001)

    work page 2001

  25. [25]

    Abeet al.(Belle Collaboration), Phys

    K. Abeet al.(Belle Collaboration), Phys. Rev. Lett.87, 091801 (2001)

    work page 2001

  26. [26]

    Aaijet al.(LHCb Collaboration), Phys

    R. Aaijet al.(LHCb Collaboration), Phys. Rev. Lett.122, 211803 (2019)

    work page 2019

  27. [27]

    J. F. Donoghue and S. Pakvasa, Phys. Rev. Lett.55, 162 (1985)

    work page 1985

  28. [28]

    J. F. Donoghue, X. G. He and S. Pakvasa, Phys. Rev. D34, 833 6 (1986)

    work page 1986

  29. [29]

    X. G. He, J. Tandean and G. Valencia, Sci. Bull.67, 1840 (2022)

    work page 2022

  30. [30]

    Ablikimet al.(BESIII Collaboration), Chin

    M. Ablikimet al.(BESIII Collaboration), Chin. Phys. C48, 093001 (2024)

    work page 2024

  31. [31]

    Y . F. Wang, Int. J. Mod. Phys. A21, 5371 (2006)

    work page 2006

  32. [32]

    Ablikimet al.(BESIII Collaboration), Nucl

    M. Ablikimet al.(BESIII Collaboration), Nucl. Instrum. Meth. A614, 345 (2010)

    work page 2010

  33. [33]

    Perotti, G

    E. Perotti, G. F ¨aldt, A. Kupsc, S. Leupold and J. J. Song, Phys. Rev. D99, 056008 (2019)

    work page 2019

  34. [34]

    F ¨aldt and A

    G. F ¨aldt and A. Kupsc, Phys. Lett. B772, 16 (2017)

    work page 2017

  35. [35]

    Jadach, B

    S. Jadach, B. F. L. Ward and Z. Was, Comput. Phys. Commun. 130, 260 (2000)

    work page 2000

  36. [36]

    Jadach, B

    S. Jadach, B. F. L. Ward and Z. Was, Phys. Rev. D63, 113009 (2001)

    work page 2001

  37. [37]

    D. J. Lange, Nucl. Instrum. Meth. A462, 152 (2001)

    work page 2001

  38. [38]

    R. G. Ping, Chin. Phys. C32, 599 (2008)

    work page 2008

  39. [39]

    Navaset al.(Particle Data Group), Phys

    S. Navaset al.(Particle Data Group), Phys. Rev. D110, 030001 (2024)

    work page 2024

  40. [40]

    J. C. Chen, G. S. Huang, X. R. Qi, D. H. Zhang and Y . S. Zhu, Phys. Rev. D62, 034003 (2000)

    work page 2000

  41. [41]

    Agostinelliet al.(GEANT4 Collaboration), Nucl

    S. Agostinelliet al.(GEANT4 Collaboration), Nucl. Instrum. Meth. Phys. Res., Sect. A506, 250 (2003)

    work page 2003

  42. [42]

    Z. Y . Deng et al., Chin. Phys. C30, 371 (2006)

    work page 2006

  43. [43]

    R. L. Yang, R. G. Ping and H. Chen, Chin. Phys. Lett.31, 061301 (2014)

    work page 2014

  44. [44]

    X. Zhou, S. Du, G. Li and C. Shen, Comput. Phy. Commun. 258, 107540 (2021)

    work page 2021

  45. [45]

    James and M

    F. James and M. Roos, Comput. Phys. Commun.10, 343 (1975)

    work page 1975

  46. [46]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D100, 051101 (2019)

    work page 2019

  47. [47]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. Lett.124, 032002 (2020)

    work page 2020

  48. [48]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D103, 012005 (2021)

    work page 2021

  49. [49]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Lett. B820, 136557 (2021)

    work page 2021

  50. [50]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D104, L091104 (2021)

    work page 2021

  51. [51]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D104, 092012 (2021)

    work page 2021

  52. [52]

    Ablikimet al.(BESIII Collaboration), JHEP06(2022) 74

    M. Ablikimet al.(BESIII Collaboration), JHEP06(2022) 74

    work page 2022

  53. [53]

    Ablikimet al.(BESIII Collaboration), Phys

    M. Ablikimet al.(BESIII Collaboration), Phys. Rev. D87, 012002 (2013)

    work page 2013

  54. [54]

    Salone, P

    N. Salone, P. Adlarson, V . Batozskaya, A. Kupsc, S. Leupold and J. Tandean, Phys. Rev. D105, 116022 (2022). M. Ablikim1 , M. N. Achasov4,d , P. Adlarson81 , X. C. Ai86 , R. Aliberti38 , A. Amoroso80A,80C , Q. An63,77,a, Y . Bai61 , O. Bakina39 , Y . Ban49,i , H.-R. Bao69 , V . Batozskaya1,47 , K. Begzsuren35, N. Berger38 , M. Berlowski47 , M. B. Bertani3...

    work page 2022