pith. sign in

arxiv: 2309.04139 · v1 · submitted 2023-09-08 · ✦ hep-ex

Novel method to extract the femtometer structure of strange baryons using the vacuum polarization effect

BESIII Collaboration: M. Ablikim , M. N. Achasov , P. Adlarson , M. Albrecht , R. Aliberti , A. Amoroso , M. R. An , Q. An
show 566 more authors
Y. Bai O. Bakina R. Baldini Ferroli I. Balossino Y. Ban V. Batozskaya D. Becker K. Begzsuren N. Berger M. Bertani D. Bettoni F. Bianchi E. Bianco J. Bloms A. Bortone I. Boyko R. A. Briere A. Brueggemann H. Cai X. Cai A. Calcaterra G. F. Cao N. Cao S. A. Cetin J. F. Chang W. L. Chang G. R. Che G. Chelkov C. Chen Chao Chen G. Chen H. S. Chen M. L. Chen S. J. Chen S. M. Chen T. Chen X. R. Chen X. T. Chen Y. B. Chen Z. J. Chen W. S. Cheng S. K. Choi X. Chu G. Cibinetto F. Cossio J. J. Cui H. L. Dai J. P. Dai A. Dbeyssi R. E. de Boer D. Dedovich Z. Y. Deng A. Denig I. Denysenko M. Destefanis F. De Mori Y. Ding J. Dong L. Y. Dong M. Y. Dong X. Dong S. X. Du Z. H. Duan P. Egorov Y. L. Fan J. Fang S. S. Fang W. X. Fang Y. Fang R. Farinelli L. Fava F. Feldbauer G. Felici C. Q. Feng J. H. Feng K Fischer M. Fritsch C. Fritzsch C. D. Fu H. Gao Y. N. Gao Yang Gao S. Garbolino I. Garzia P. T. Ge Z. W. Ge C. Geng E. M. Gersabeck A Gilman K. Goetzen L. Gong W. X. Gong W. Gradl M. Greco L. M. Gu M. H. Gu Y. T. Gu C. Y Guan A. Q. Guo L. B. Guo R. P. Guo Y. P. Guo A. Guskov W. Y. Han X. Q. Hao F. A. Harris K. K. He K. L. He F. H. Heinsius C. H. Heinz Y. K. Heng C. Herold G. Y. Hou Y. R. Hou Z. L. Hou H. M. Hu J. F. Hu T. Hu Y. Hu G. S. Huang K. X. Huang L. Q. Huang X. T. Huang Y. P. Huang Z. Huang T. Hussain N H\"usken W. Imoehl M. Irshad J. Jackson S. Jaeger S. Janchiv E. Jang J. H. Jeong Q. Ji Q. P. Ji X. B. Ji X. L. Ji Y. Y. Ji Z. K. Jia P. C. Jiang S. S. Jiang X. S. Jiang Y. Jiang J. B. Jiao Z. Jiao S. Jin Y. Jin M. Q. Jing T. Johansson S. Kabana N. Kalantar-Nayestanaki X. L. Kang X. S. Kang R. Kappert M. Kavatsyuk B. C. Ke I. K. Keshk A. Khoukaz R. Kiuchi R. Kliemt L. Koch O. B. Kolcu B. Kopf M. Kuemmel M. Kuessner A. Kupsc W. K\"uhn J. J. Lane J. S. Lange P. Larin A. Lavania L. Lavezzi T. T. Lei Z. H. Lei H. Leithoff M. Lellmann T. Lenz C. Li C. H. Li Cheng Li D. M. Li F. Li G. Li H. Li H. B. Li H. J. Li H. N. Li J. Q. Li J. S. Li J. W. Li Ke Li L. J Li L. K. Li Lei Li M. H. Li P. R. Li S. X. Li S. Y. Li T. Li W. D. Li W. G. Li X. H. Li X. L. Li Xiaoyu Li Y. G. Li Z. X. Li Z. Y. Li C. Liang H. Liang Y. F. Liang Y. T. Liang G. R. Liao L. Z. Liao J. Libby A. Limphirat C. X. Lin D. X. Lin T. Lin B. J. Liu C. Liu C. X. Liu D. Liu F. H. Liu Fang Liu Feng Liu G. M. Liu H. Liu H. B. Liu H. M. Liu Huanhuan Liu Huihui Liu J. B. Liu J. L. Liu J. Y. Liu K. Liu K. Y. Liu Ke Liu L. Liu Lu Liu M. H. Liu P. L. Liu Q. Liu S. B. Liu T. Liu W. K. Liu W. M. Liu X. Liu Y. Liu Y. B. Liu Z. A. Liu Z. Q. Liu X. C. Lou F. X. Lu H. J. Lu J. G. Lu X. L. Lu Y. Lu Y. P. Lu Z. H. Lu C. L. Luo M. X. Luo T. Luo X. L. Luo X. R. Lyu Y. F. Lyu F. C. Ma H. L. Ma L. L. Ma M. M. Ma Q. M. Ma R. Q. Ma R. T. Ma X. Y. Ma Y. Ma F. E. Maas M. Maggiora S. Maldaner S. Malde Q. A. Malik A. Mangoni Y. J. Mao Z. P. Mao S. Marcello Z. X. Meng J. G. Messchendorp G. Mezzadri H. Miao T. J. Min R. E. Mitchell X. H. Mo N. Yu. Muchnoi Y. Nefedov F. Nerling I. B. Nikolaev Z. Ning S. Nisar Y. Niu S. L. Olsen Q. Ouyang S. Pacetti X. Pan Y. Pan A. Pathak Y. P. Pei M. Pelizaeus H. P. Peng K. Peters J. L. Ping R. G. Ping S. Plura S. Pogodin V. Prasad F. Z. Qi H. Qi H. R. Qi M. Qi T. Y. Qi S. Qian W. B. Qian Z. Qian C. F. Qiao J. J. Qin L. Q. Qin X. P. Qin X. S. Qin Z. H. Qin J. F. Qiu S. Q. Qu K. H. Rashid C. F. Redmer K. J. Ren A. Rivetti V. Rodin M. Rolo G. Rong Ch. Rosner S. N. Ruan A. Sarantsev Y. Schelhaas C. Schnier K. Schoenning M. Scodeggio K. Y. Shan W. Shan X. Y. Shan J. F. Shangguan L. G. Shao M. Shao C. P. Shen H. F. Shen W. H. Shen X. Y. Shen B. A. Shi H. C. Shi J. Y. Shi Q. Q. Shi R. S. Shi X. Shi J. J. Song W. M. Song Y. X. Song S. Sosio S. Spataro F. Stieler P. P. Su Y. J. Su G. X. Sun H. Sun H. K. Sun J. F. Sun L. Sun S. S. Sun T. Sun W. Y. Sun Y. J. Sun Y. Z. Sun Z. T. Sun Y. X. Tan C. J. Tang G. Y. Tang J. Tang L. Y Tao Q. T. Tao M. Tat J. X. Teng V. Thoren W. H. Tian Y. Tian I. Uman B. Wang B. L. Wang C. W. Wang D. Y. Wang F. Wang H. J. Wang H. P. Wang K. Wang L. L. Wang M. Wang M. Z. Wang Meng Wang S. Wang T. Wang T. J. Wang W. Wang W. H. Wang W. P. Wang X. Wang X. F. Wang X. L. Wang Y. Wang Y. D. Wang Y. F. Wang Y. H. Wang Y. Q. Wang Yaqian Wang Z. Wang Z. Y. Wang Ziyi Wang D. H. Wei F. Weidner S. P. Wen D. J. White U. Wiedner G. Wilkinson M. Wolke L. Wollenberg J. F. Wu L. H. Wu L. J. Wu X. Wu X. H. Wu Y. Wu Y. J Wu Z. Wu L. Xia T. Xiang D. Xiao G. Y. Xiao H. Xiao S. Y. Xiao Y. L. Xiao Z. J. Xiao C. Xie X. H. Xie Y. Xie Y. G. Xie Y. H. Xie Z. P. Xie T. Y. Xing C. F. Xu C. J. Xu G. F. Xu H. Y. Xu Q. J. Xu X. P. Xu Y. C. Xu Z. P. Xu F. Yan L. Yan W. B. Yan W. C. Yan H. J. Yang H. L. Yang H. X. Yang S. L. Yang Tao Yang Y. F. Yang Y. X. Yang Yifan Yang M. Ye M. H. Ye J. H. Yin Z. Y. You B. X. Yu C. X. Yu G. Yu T. Yu X. D. Yu C. Z. Yuan L. Yuan S. C. Yuan X. Q. Yuan Y. Yuan Z. Y. Yuan C. X. Yue A. A. Zafar F. R. Zeng X. Zeng Y. Zeng X. Y. Zhai Y. H. Zhan A. Q. Zhang B. L. Zhang B. X. Zhang D. H. Zhang G. Y. Zhang H. Zhang H. H. Zhang H. Q. Zhang H. Y. Zhang J. L. Zhang J. Q. Zhang J. W. Zhang J. X. Zhang J. Y. Zhang J. Z. Zhang Jianyu Zhang Jiawei Zhang L. M. Zhang L. Q. Zhang Lei Zhang P. Zhang Q. Y. Zhang Shuihan Zhang Shulei Zhang X. D. Zhang X. M. Zhang X. Y. Zhang Y. Zhang Y. T. Zhang Y. H. Zhang Yan Zhang Yao Zhang Z. H. Zhang Z. L. Zhang Z. Y. Zhang G. Zhao J. Zhao J. Y. Zhao J. Z. Zhao Lei Zhao Ling Zhao M. G. Zhao S. J. Zhao Y. B. Zhao Y. X. Zhao Z. G. Zhao A. Zhemchugov B. Zheng J. P. Zheng W. J. Zheng Y. H. Zheng B. Zhong C. Zhong X. Zhong H. Zhou L. P. Zhou X. Zhou X. K. Zhou X. R. Zhou X. Y. Zhou Y. Z. Zhou J. Zhu K. Zhu K. J. Zhu L. X. Zhu S. H. Zhu S. Q. Zhu T. J. Zhu W. J. Zhu Y. C. Zhu Z. A. Zhu J. H. Zou J. Zu
This is my paper

Pith reviewed 2026-05-24 06:38 UTC · model grok-4.3

classification ✦ hep-ex
keywords electromagnetic form factorsstrange baryonsvacuum polarizationJ/psi resonancehyperon structureCP symmetryBESIII
0
0 comments X

The pith

Vacuum polarization at the J/psi resonance extracts the electromagnetic form factor ratio and phases of strange baryons.

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

The paper introduces a method that uses the cross-section enhancement from vacuum polarization when electron-positron collisions produce hyperon-antihyperon pairs at the J/psi resonance. With ten billion J/psi events, the approach determines the ratio of electromagnetic form factors and the relative phases for bar Lambda Sigma0 and Lambda bar Sigma0 pairs. These quantities encode the charge and magnetization distributions inside the hyperons at femtometer scales. The same data set shows that charge-parity violation in the reaction is consistent with exact symmetry.

Core claim

The vacuum polarization effect at the J/psi allows extraction of the form factor ratio R = 0.860 ± 0.029 (stat.) ± 0.010 (syst.) together with phases ΔΦ1 = 1.011 ± 0.094 (stat.) ± 0.010 (syst.) rad for bar Lambda Sigma0 and ΔΦ2 = 2.128 ± 0.094 (stat.) ± 0.010 (syst.) rad for Lambda bar Sigma0, while the reaction exhibits no detectable CP breaking beyond symmetry.

What carries the argument

The vacuum polarization effect at the J/psi resonance, which produces a measurable cross-section enhancement that directly encodes the hyperon electromagnetic structure in the extracted ratio and phases.

If this is right

  • The method supplies a direct snapshot of the charge and magnetization distributions inside Lambda and Sigma0 baryons during pair production.
  • It supplies the first experimental check of CP symmetry in this specific hyperon reaction channel.
  • The same resonance-enhancement technique can be applied to other hyperon pairs to map their structures.

Where Pith is reading between the lines

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

  • The measured phases may serve as benchmarks for theoretical calculations of baryon wave functions in the strange sector.
  • If the method generalizes cleanly, repeated measurements at multiple resonances could test whether the extracted structures remain stable or vary with energy.
  • Discrepancies between this ratio and results from other production channels would indicate additional dynamical contributions not captured by the vacuum-polarization picture.

Load-bearing premise

The observed cross-section enhancement is caused entirely by vacuum polarization at the J/psi resonance with no significant contribution from other mechanisms or backgrounds.

What would settle it

An independent measurement at a different energy away from the J/psi resonance, or a detailed background study showing sizable non-vacuum-polarization contributions that shift the extracted ratio or phases, would falsify the attribution.

Figures

Figures reproduced from arXiv: 2309.04139 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. Lavania, A. Limphirat, A. Mangoni, A. Pathak, A. Q. Guo, A. Q. Zhang, A. Rivetti, A. Sarantsev, A. Zhemchugov, B. A. Shi, B. C. Ke, BESIII Collaboration: M. Ablikim, B. J. Liu, B. Kopf, B. L. Wang, B. L. Zhang, B. Wang, B. X. Yu, B. X. Zhang, B. Zheng, B. Zhong, C. Chen, C. D. Fu, C. F. Qiao, C. F. Redmer, C. Fritzsch, C. F. Xu, C. Geng, Chao Chen, Cheng Li, C. Herold, C. H. Heinz, C. H. Li, Ch. Rosner, C. J. Tang, C. J. Xu, C. Li, C. Liang, C. Liu, C. L. Luo, C. P. Shen, C. Q. Feng, C. Schnier, C. W. Wang, C. Xie, C. X. Lin, C. X. Liu, C. X. Yu, C. X. Yue, C. Y Guan, C. Zhong, C. Z. Yuan, D. Becker, D. Bettoni, D. Dedovich, D. H. Wei, D. H. Zhang, D. J. White, D. Liu, D. M. Li, D. Xiao, D. X. Lin, D. Y. Wang, E. Bianco, E. Jang, E. M. Gersabeck, F. A. Harris, Fang Liu, F. Bianchi, F. C. Ma, F. Cossio, F. De Mori, F. E. Maas, Feng Liu, F. Feldbauer, F. H. Heinsius, F. H. Liu, F. Li, F. Nerling, F. R. Zeng, F. Stieler, F. Wang, F. Weidner, F. X. Lu, F. Yan, F. Z. Qi, G. Chelkov, G. Chen, G. Cibinetto, G. F. Cao, G. Felici, 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. Li, H. B. Liu, H. Cai, H. C. Shi, 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. Leithoff, H. Li, H. Liang, H. Liu, H. L. Ma, H. L. Yang, H. M. Hu, H. Miao, H. M. Liu, H. N. Li, H. P. Peng, H. P. Wang, H. Qi, H. Q. Zhang, H. R. Qi, H. S. Chen, H. Sun, Huanhuan Liu, Huihui Liu, H. Xiao, H. X. Yang, H. Y. Xu, H. Y. Zhang, H. Zhang, H. Zhou, I. Balossino, I. B. Nikolaev, I. Boyko, I. Denysenko, I. Garzia, I. K. Keshk, I. Uman, J. B. Jiao, J. B. Liu, J. Bloms, 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. G. Messchendorp, J. H. Feng, J. H. Jeong, J. H. Yin, J. H. Zou, Jianyu Zhang, Jiawei Zhang, J. Jackson, J. J. Cui, J. J. Lane, J. J. Qin, J. J. Song, J. Libby, J. L. Liu, J. L. Ping, J. L. Zhang, J. P. Dai, J. P. Zheng, J. Q. Li, J. Q. Zhang, J. S. Lange, J. S. Li, J. Tang, J. W. Li, J. W. Zhang, J. X. Teng, J. X. Zhang, J. Y. Liu, J. Y. Shi, J. Y. Zhang, J. Y. Zhao, J. Zhao, J. Zhu, J. Zu, J. Z. Zhang, J. Z. Zhao, K. Begzsuren, Ke Li, Ke Liu, K Fischer, K. Goetzen, K. H. Rashid, K. J. Ren, K. J. Zhu, K. K. He, K. L. He, K. Liu, K. Peters, K. Schoenning, K. Wang, K. X. Huang, K. Y. Liu, K. Y. Shan, K. Zhu, L. B. Guo, Lei Li, Lei Zhang, Lei Zhao, L. Fava, L. Gong, L. G. Shao, L. H. Wu, Ling Zhao, L. J Li, L. J. Wu, L. K. Li, L. Koch, L. Lavezzi, L. Liu, L. L. Ma, L. L. Wang, L. M. Gu, L. M. Zhang, L. P. Zhou, L. Q. Huang, L. Q. Qin, L. Q. Zhang, L. Sun, Lu Liu, L. Wollenberg, L. Xia, L. X. Zhu, L. Yan, L. Y. Dong, L. Y Tao, L. Yuan, L. Z. Liao, M. Albrecht, M. Bertani, M. Destefanis, Meng Wang, M. Fritsch, M. Greco, M. G. Zhao, M. H. Gu, M. H. Li, M. H. Liu, M. H. Ye, M. Irshad, M. Kavatsyuk, M. Kuemmel, M. Kuessner, M. L. Chen, M. Lellmann, M. Maggiora, M. M. Ma, M. N. Achasov, M. Pelizaeus, M. Qi, M. Q. Jing, M. R. An, M. Rolo, M. Scodeggio, M. Shao, M. Tat, M. Wang, M. Wolke, M. X. Luo, M. Y. Dong, M. Ye, M. Z. Wang, N. Berger, N. Cao, N H\"usken, N. Kalantar-Nayestanaki, N. Yu. Muchnoi, O. Bakina, O. B. Kolcu, P. Adlarson, P. C. Jiang, P. Egorov, P. Larin, P. L. Liu, P. P. Su, P. R. Li, P. T. Ge, P. Zhang, Q. A. Malik, Q. An, Q. Ji, Q. J. Xu, Q. Liu, Q. M. Ma, Q. Ouyang, Q. P. Ji, Q. Q. Shi, Q. T. Tao, Q. Y. Zhang, R. A. Briere, R. Aliberti, R. Baldini Ferroli, R. E. de Boer, R. E. Mitchell, R. Farinelli, R. G. Ping, R. Kappert, R. Kiuchi, R. Kliemt, R. P. Guo, R. Q. Ma, R. S. Shi, R. T. Ma, S. A. Cetin, S. B. Liu, S. C. Yuan, S. Garbolino, Shuihan Zhang, Shulei Zhang, S. H. Zhu, S. Jaeger, S. Janchiv, S. J. Chen, S. Jin, S. J. Zhao, S. Kabana, S. K. Choi, S. L. Olsen, S. L. Yang, S. Maldaner, S. Malde, S. Marcello, S. M. Chen, S. Nisar, S. N. Ruan, S. Pacetti, S. Plura, S. Pogodin, S. P. Wen, S. Qian, S. Q. Qu, S. Q. Zhu, S. S. Fang, S. S. Jiang, S. Sosio, S. Spataro, S. S. Sun, S. Wang, S. X. Du, S. X. Li, S. Y. Li, S. Y. Xiao, Tao Yang, T. Chen, T. Hu, T. Hussain, T. J. Min, T. Johansson, T. J. Wang, T. J. Zhu, T. Lenz, T. Li, T. Lin, T. Liu, T. Luo, T. Sun, T. T. Lei, T. Wang, T. Xiang, T. Y. Qi, T. Yu, T. Y. Xing, U. Wiedner, V. Batozskaya, V. Prasad, V. Rodin, V. Thoren, W. B. Qian, W. B. Yan, W. C. Yan, W. D. Li, W. G. Li, W. Gradl, W. H. Shen, W. H. Tian, W. H. Wang, W. Imoehl, W. J. Zheng, W. J. Zhu, W. K. Liu, W. K\"uhn, W. L. Chang, W. M. Liu, W. M. Song, W. P. Wang, W. S. Cheng, W. Shan, W. Wang, W. X. Fang, W. X. Gong, W. Y. Han, W. Y. Sun, X. B. Ji, X. Cai, X. Chu, X. C. Lou, X. Dong, X. D. Yu, X. D. Zhang, X. F. Wang, X. H. Li, X. H. Mo, X. H. Wu, X. H. Xie, Xiaoyu Li, X. K. Zhou, X. Liu, X. L. Ji, X. L. Kang, X. L. Li, X. L. Lu, X. L. Luo, X. L. Wang, X. M. Zhang, X. Pan, X. P. Qin, X. P. Xu, X. Q. Hao, X. Q. Yuan, X. R. Chen, X. R. Lyu, X. R. Zhou, X. Shi, X. S. Jiang, X. S. Kang, X. S. Qin, X. T. Chen, X. T. Huang, X. Wang, X. Wu, X. Y. Ma, X. Y. Shan, X. Y. Shen, X. Y. Zhai, X. Y. Zhang, X. Y. Zhou, X. Zeng, X. Zhong, X. Zhou, Yang Gao, Yan Zhang, Yao Zhang, Yaqian Wang, Y. Bai, Y. Ban, Y. B. Chen, Y. B. Liu, Y. B. Zhao, Y. C. Xu, Y. C. Zhu, Y. Ding, Y. D. Wang, Y. Fang, Y. F. Liang, Y. F. Lyu, Y. F. Wang, Y. F. Yang, Y. G. Li, Y. G. Xie, Y. Hu, Y. H. Wang, Y. H. Xie, Y. H. Zhan, Y. H. Zhang, Y. H. Zheng, Yifan Yang, Y. Jiang, Y. Jin, Y. J. Mao, Y. J. Su, Y. J. Sun, Y. J Wu, Y. K. Heng, Y. L. Fan, Y. Liu, Y. Lu, Y. L. Xiao, Y. Ma, Y. Nefedov, Y. N. Gao, Y. Niu, Y. Pan, Y. P. Guo, Y. P. Huang, Y. P. Lu, Y. P. Pei, Y. Q. Wang, Y. R. Hou, Y. Schelhaas, Y. T. Gu, Y. Tian, Y. T. Liang, Y. T. Zhang, Y. Wang, Y. Wu, Y. Xie, Y. X. Song, Y. X. Tan, Y. X. Yang, Y. X. Zhao, Y. Y. Ji, Y. Yuan, Y. Zeng, Y. Zhang, Y. Z. Sun, Y. Z. Zhou, Z. A. Liu, Z. A. Zhu, Z. G. Zhao, Z. H. Duan, Z. H. Lei, Z. H. Lu, Z. H. Qin, Z. Huang, Z. H. Zhang, Ziyi Wang, Z. J. Chen, Z. Jiao, Z. J. Xiao, Z. K. Jia, Z. L. Hou, Z. L. Zhang, Z. Ning, Z. P. Mao, Z. P. Xie, Z. P. Xu, Z. Qian, Z. Q. Liu, Z. T. Sun, Z. Wang, Z. W. Ge, Z. Wu, Z. X. Li, Z. X. Meng, Z. Y. Deng, Z. Y. Li, Z. Y. Wang, Z. Y. You, Z. Y. Yuan, Z. Y. Zhang.

Figure 1
Figure 1. Figure 1: FIG. 1. The Feynman diagrams for [PITH_FULL_IMAGE:figures/full_fig_p005_1.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3. Fit to the [PITH_FULL_IMAGE:figures/full_fig_p006_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: FIG. 4. Fit to the [PITH_FULL_IMAGE:figures/full_fig_p006_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: FIG. 5. Definition of the helicity angles for [PITH_FULL_IMAGE:figures/full_fig_p007_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: FIG. 6. Fit results compared with data of [PITH_FULL_IMAGE:figures/full_fig_p008_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: FIG. 7. Fit results compared with data of [PITH_FULL_IMAGE:figures/full_fig_p008_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: FIG. 8. Polarization [PITH_FULL_IMAGE:figures/full_fig_p009_8.png] view at source ↗
read the original abstract

One of the fundamental goals of particle physics is to gain microscopic understanding of the strong interaction. Electromagnetic form factors quantify the structure of hadrons in terms of charge and magnetization distributions. While the nucleon structure has been investigated extensively, data on hyperons is still scarce. It has recently been demonstrated that electron-positron annihilations into hyperon-antihyperon pairs provide a powerful tools to investigate their inner structure. We present a novel method useful for hyperon-antihyperon pairs of different types which exploits the cross section enhancement due to the vacuum polarization effect at the $J/\psi$ resonance. Using the 10 billion $J/\psi$ events collected with the BESIII detector, this allows a thorough determination of the hyperon structure . The result is essentially a precise snapshot of a $\bar\Lambda\Sigma^0$~($\Lambda\bar\Sigma^0$) pair in the making, encoded in the form factor ratio and the phase. Their values are measured to be $R = 0.860\pm0.029({\rm stat.})\pm0.010({\rm syst.})$, $\Delta\Phi_1=(1.011\pm0.094({\rm stat.})\pm0.010({\rm syst.}))~\rm rad$ for $\bar\Lambda\Sigma^0$ and $\Delta\Phi_2=(2.128\pm0.094({\rm stat.})\pm0.010({\rm syst.}))~\rm rad$ for $\Lambda\bar\Sigma^0$, respectively. Furthermore, charge-parity (CP) breaking is investigated for the first time in this reaction and found to be consistent with CP symmetry.

Editorial analysis

A structured set of objections, weighed in public.

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 / 1 minor

Summary. The manuscript proposes a novel method to extract electromagnetic form factors of strange baryons by exploiting cross-section enhancement from the vacuum polarization effect at the J/ψ resonance in e⁺e⁻ annihilations into hyperon-antihyperon pairs. Using 10 billion J/ψ events collected with BESIII, the authors report R = 0.860 ± 0.029 (stat.) ± 0.010 (syst.), ΔΦ₁ = 1.011 ± 0.094 (stat.) ± 0.010 (syst.) rad for Λ̄Σ⁰, and ΔΦ₂ = 2.128 ± 0.094 (stat.) ± 0.010 (syst.) rad for ΛΣ̄⁰, while finding CP violation consistent with zero.

Significance. If the central attribution holds, the work supplies new experimental constraints on hyperon structure at a specific energy point where data remain scarce. The 10-billion-event sample and separate reporting of statistical and systematic uncertainties are clear strengths, enabling a direct extraction rather than a parameter fit internal to the dataset.

major comments (1)
  1. [Method and analysis description] The extraction of R and the phases assumes the observed enhancement arises entirely from vacuum polarization on the virtual-photon propagator. The manuscript must demonstrate that direct J/ψ decays, non-resonant continuum contributions, final-state interactions, and unmodeled backgrounds alter the angular distributions or effective cross section by amounts smaller than the quoted uncertainties; without such quantitative bounds the central claim cannot be verified.
minor comments (1)
  1. [Abstract] The abstract states that the result is 'essentially a precise snapshot' but does not quote the precise center-of-mass energy or Q² value at which the form factors are determined.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the detailed review and constructive feedback. The single major comment is addressed below. We agree that explicit quantitative bounds on potential contaminations strengthen the central claim and will incorporate them in the revision.

read point-by-point responses

  1. Referee: [Method and analysis description] The extraction of R and the phases assumes the observed enhancement arises entirely from vacuum polarization on the virtual-photon propagator. The manuscript must demonstrate that direct J/ψ decays, non-resonant continuum contributions, final-state interactions, and unmodeled backgrounds alter the angular distributions or effective cross section by amounts smaller than the quoted uncertainties; without such quantitative bounds the central claim cannot be verified.

    Authors: We agree that the manuscript should provide explicit quantitative bounds to confirm that the observed enhancement is dominated by the vacuum-polarization effect. The current analysis already subtracts non-resonant continuum contributions using off-resonance data samples and applies selection criteria that suppress direct J/ψ decays into the same final states. Final-state interactions are incorporated via the angular-distribution parametrization. However, to meet the referee's request for numerical verification, we will add a dedicated subsection in the revised manuscript. This subsection will report: (i) upper limits on direct J/ψ decay contributions derived from known branching fractions and reconstruction efficiencies, (ii) estimates of residual continuum and background effects from sideband studies, and (iii) theoretical bounds on final-state interaction corrections showing that each source shifts R and the phases by amounts well below the quoted statistical and systematic uncertainties. These additions will be supported by supplementary tables and figures. revision: yes

Circularity Check

0 steps flagged

No circularity; experimental extraction from collision data with independent analysis chain

full rationale

The paper reports a direct experimental measurement of hyperon form-factor ratio R and relative phases ΔΦ from 10 billion J/ψ events collected at BESIII. The central results are obtained by fitting angular distributions in the observed e⁺e⁻ → ΛΣ⁰ (and charge conjugate) final states after attributing the resonant enhancement to vacuum polarization of the virtual photon propagator. No derivation chain, ansatz, or uniqueness theorem is invoked that reduces the extracted parameters to quantities fitted inside the same dataset or to self-citations. The analysis assumptions (negligible contamination from direct J/ψ decays or other mechanisms) are external to the fitted values themselves and are subject to standard experimental validation rather than being tautological. This matches the default expectation for a data-driven measurement paper whose output is not equivalent to its inputs by construction.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The measurement rests on the domain assumption that vacuum polarization produces a clean, quantifiable enhancement usable for form-factor extraction, plus standard particle-physics assumptions about resonance lineshapes and form-factor parameterization; no new free parameters or invented entities are introduced beyond the fitted observables themselves.

axioms (1)
  • domain assumption Vacuum polarization at the J/psi resonance produces a measurable and dominant enhancement in the hyperon-pair cross section that can be isolated from other contributions.
    This is the enabling premise for the novel method described in the abstract.

pith-pipeline@v0.9.0 · 8921 in / 1394 out tokens · 54045 ms · 2026-05-24T06:38:48.091407+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

What do these tags mean?
matches
The paper's claim is directly supported by a theorem in the formal canon.
supports
The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
extends
The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
uses
The paper appears to rely on the theorem as machinery.
contradicts
The paper's claim conflicts with a theorem or certificate in the canon.
unclear
Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.

Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Tests of CP symmetry in entangled hyperon anti-hyperon pairs at BESIII

    hep-ex 2025-01 unverdicted novelty 1.0

    A review summarizing progress on CP asymmetry measurements in Lambda, Sigma, and Xi hyperon pairs from BESIII charmonium data.

Reference graph

Works this paper leans on

56 extracted references · 56 canonical work pages · cited by 1 Pith paper

  1. [1]

    The geant4-based [38] MC pack- age includes the geometric description of the BESIII detector and the detector response

    Monte Carlo simulation The optimization of the event selection criteria and the estimation of physics background as well as the determination of efficiency are performed using MC simulated samples. The geant4-based [38] MC pack- age includes the geometric description of the BESIII detector and the detector response. The inclusive MC sample includes both t...

    work page

  2. [2]

    Charged tracks are selected in the MDC within ±20 cm of the interaction point in the beam direction and within 10 cm in the plane perpendicular to the beam

    Initial Selection Criteria Candidates for J/ψ → ¯Λ(→ ¯pπ+) Σ 0(→ γΛ → γpπ −) are required to have four charged tracks with net zero charge and at least one photon. Charged tracks are selected in the MDC within ±20 cm of the interaction point in the beam direction and within 10 cm in the plane perpendicular to the beam. The polar angles of these tracks are...

    work page

  3. [3]

    2, where the clear cluster corresponds to the de- cays of Λ → pπ− and ¯Λ → ¯pπ+

    Final Selection Criteria After the initial selection, the scatter plot of Mpπ− versus M¯pπ+ of the accepted candidates is shown in Fig. 2, where the clear cluster corresponds to the de- cays of Λ → pπ− and ¯Λ → ¯pπ+. The Λ and ¯Λ signal candidates are selected by requiring |Mpπ− −MΛ| < 5 MeV/c2 and |M¯pπ+ − MΛ| < 5 MeV/ c2. To further suppress backgrounds...

    work page

  4. [4]

    Background Analysis Possible background sources are investigated with an inclusive MC sample of 10 billion J/ψ decays. Using the same selection criteria, with the help of a generic event type analysis tool [46], the surviv- ing background events mainly originate from J/ψ → Σ0 ¯Σ0, J/ψ → Λ¯Λ and J/ψ → γΛ¯Λ (including a res- onant contribution from γηc), bu...

    work page

  5. [5]

    The total probability density func- tion (PDF) consists of a signal and various back- ground contributions

    Signal Extraction The signal yields are obtained from an extended unbinned maximum likelihood fit to the γΛ ( γ ¯Λ) mass spectrum. The total probability density func- tion (PDF) consists of a signal and various back- ground contributions. The signal component is mod- eled as the MC simulated signal shape convolved with a Gaussian function to account for t...

    work page

  6. [6]

    Helicity Amplitude The structure of the six dimensional angular dis- tribution is determined by global parameters ω = (αJ/ψ, ∆Φ, αγ, αΛ, α¯Λ) independent of the Σ 0 scat- tering angle, θΣ0, and is written in a modular form as W (ξ; ω) = 3X µ,ν=0 3X µ′=0 CµνaΣ0 µµ′aΛ µ′0a ¯Λ ν0 , (A2) where the Cµν(θ; αJ/ψ, ∆Φ) is a 4 × 4 spin density matrix, describing th...

    work page

  7. [7]

    A simul- taneous fit is performed to the two conjugate chan- nels, J/ψ → ¯ΛΣ0 and J/ψ → Λ¯Σ0

    Global Fit of Parameters A non-zero phase angle difference ∆Φ indicates the transverse hyperon polarization, which allows us to measure these parameters at the same time. A simul- taneous fit is performed to the two conjugate chan- nels, J/ψ → ¯ΛΣ0 and J/ψ → Λ¯Σ0. The likeli- hood function constructed from the probability den- sity function for an event c...

    work page

  8. [8]

    For the Λ, ¯Λ reconstruction, a correction to the MC effi- ciency is made

    Systematic Uncertainty The uncertainties in the measurement of the form factors are mainly from the Λ , ¯Λ reconstruction, the 4C kinematic fit, and the background estimation. For the Λ, ¯Λ reconstruction, a correction to the MC effi- ciency is made. We also use the control sample of J/ψ → ¯pK+Λ to obtain the efficiencies of the data and MC simulation in ...

    work page

  9. [9]

    R. W. McAllister and R. Hofstadter, Phys. Rev. 102, 851 (1956)

    work page 1956

  10. [10]

    Punjabi, C

    V. Punjabi, C. F. Perdrisat, M. K. Jones, E. J. Brash and C. E. Carlson, Eur. Phys. J. A 51, 79 (1956)

    work page 1956

  11. [11]

    A. J. R. Puckett et al . (Jefferson Lab Hall A Collaboration), Phys. Rev. C 85, 045203 (2012)

    work page 2012

  12. [12]

    Ablikim et al

    M. Ablikim et al. (BESIII Collaboration), Phys. Lett. B 817, 136328 (2021)

    work page 2021

  13. [13]

    Y. H. Lin, H. W. Hammer and U. Meißner, Phys. Lett. B 816, 136254 (2021)

    work page 2021

  14. [14]

    Mangoni, S

    A. Mangoni, S. Pacetti, and E. Tomasi-Gustafsson, Phys. Rev. D 104, 116016 (2021)

    work page 2021

  15. [15]

    Segovia, I

    J. Segovia, I. C. Cloet, C. D. Roberts, and S. M. Schmidt, Few Body Syst. 55, 1185 (2014)

    work page 2014

  16. [16]

    Ablikim et al

    M. Ablikim et al . (BESIII Collaboration), Nuovo Cim. C 40, 28 (2017)

    work page 2017

  17. [17]

    Ablikim et al

    M. Ablikim et al . (BESIII Collaboration), PoS BORMIO2017, 004 (2017)

    work page 2017

  18. [18]

    Ablikim et al

    M. Ablikim et al. (BESIII Collaboration), EPJ Web Conf 192, 00023 (2018)

    work page 2018

  19. [19]

    Ablikim et al

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

    work page 2019

  20. [20]

    Ablikim et al

    M. Ablikim et al . (BESIII Collaboration), PoS ICHEP2018, 550 (2019)

    work page 2019

  21. [21]

    Ablikim et al

    M. Ablikim et al. (BESIII Collaboration), EPJ Web Conf. 199, 03009 (2019)

    work page 2019

  22. [22]

    Ablikim et al

    M. Ablikim et al . (BESIII Collaboration), PoS SPIN2018, 121 (2019)

    work page 2019

  23. [23]

    Ablikim et al

    M. Ablikim et al . (BESIII Collaboration), J. Phys. Conf. Ser. 1137, 012010 (2019)

    work page 2019

  24. [24]

    Ablikim et al

    M. Ablikim et al . (BESIII Collaboration), Nuovo Cim. C 42, 111 (2019)

    work page 2019

  25. [25]

    Ablikim et al

    M. Ablikim et al. (BESIII Collaboration), AIP Conf. Proc. 2130, 040009 (2019)

    work page 2019

  26. [26]

    Ablikim et al

    M. Ablikim et al . (BESIII Collaboration), J. Phys. Conf. Ser. 1435, 012031 (2020)

    work page 2020

  27. [27]

    Ablikim et al

    M. Ablikim et al. (BESIII Collaboration), Phys. Lett. B 814, 136110 (2021)

    work page 2021

  28. [28]

    Ablikim et al

    M. Ablikim et al. (BESIII Collaboration), Phys. Lett. B 831, 137187 (2022)

    work page 2022

  29. [29]

    Ablikim et al

    M. Ablikim et al. (BESIII Collaboration), Phys. Rev. D 106, L091101 (2022)

    work page 2022

  30. [30]

    Ablikim et al

    M. Ablikim et al. (BESIII Collaboration), Phys. Rev. Lett. 123, 122003 (2019)

    work page 2019

  31. [31]

    R. B. Ferroli, A. Mangoni, and S. Pacetti, Eur. Phys. J. C 80, 903 (2020)

    work page 2020

  32. [32]

    Perotti, Ph.D

    E. Perotti, Ph.D. thesis, Uppsala U. (2020)

    work page 2020

  33. [33]

    Ablikim et al

    M. Ablikim et al . (BESIII Collaboration), Chin. Phys. C 46, 074001 (2022)

    work page 2022

  34. [34]

    Ablikim et al

    M. Ablikim et al . (BESIII Collaboration), Nucl. Instrum. Meth. A 614, 345 (2010)

    work page 2010

  35. [35]

    C. H. Yu et al ., Proceedings of IPAC2016, Busan, Korea, 2016, doi:10.18429/JACoW-IPAC2016- TUYA01

    work page doi:10.18429/jacow-ipac2016- 2016

  36. [36]

    Ablikim et al

    M. Ablikim et al. (BESIII Collaboration), Phys. Lett. B 791, 375 (2019)

    work page 2019

  37. [37]

    A. Z. Dubnickova, S. Dubniˇ cka, and M. P. Rekalo, Nuovo Cimento A 109, 241 (1996)

    work page 1996

  38. [38]

    Pacetti, R

    S. Pacetti, R. B. Ferroli, and E. Tomasi-Gustafsson, Phys. Rep. 550, 1 (2015)

    work page 2015

  39. [39]

    F¨ aldt, and A

    G. F¨ aldt, and A. Kupsc,Phys. Lett. B 772, 16 (2017)

    work page 2017

  40. [40]

    Haidenbauer, U

    J. Haidenbauer, U. Meißner, and L. Y. Dai, Phys. Rev. D 103, 014028 (2021). 14

    work page 2021

  41. [41]

    Ablikim et al

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

    work page 2022

  42. [42]

    F¨ aldt,Phys

    G. F¨ aldt,Phys. Rev. D 97, 053002 (2018)

    work page 2018

  43. [43]

    Ablikim et al

    M. Ablikim et al . (BESIII Collaboration), Chin. Phys. C 44, 040001 (2022)

    work page 2022

  44. [44]

    Salone, P

    N. Salone, P. Adlarson, V. Batozskaya, S. Leupold, and J. Tandean, Phys. Rev. D 105, 116022 (2022)

    work page 2022

  45. [45]

    G Barucca et al., Eur. Phys. J. A 57, 154 (2021)

    work page 2021

  46. [46]

    Agostinelli et al., Nucl

    S. Agostinelli et al., Nucl. Instrum. Meth. A 506, 250 (2003)

    work page 2003

  47. [47]

    Jadach, B

    S. Jadach, B. F. L. Ward, and Z. Was, Phys. Rev. D 63, 113009 (2001); Comput. Phys. Commun. 130, 260 (2000)

    work page 2001

  48. [48]

    D. J. Lange, Nucl. Instrum. Meth. A 462, 152 (2001); R. G. Ping, Chin. Phys. C 32, 599 (2008)

    work page 2001

  49. [49]

    P. A. Zyla et al ., Prog. Theor. Exp. Phys. 2022, 083C01 (2022)

    work page 2022

  50. [50]

    J. C. Chen, G. S. Huang, X. R. Qi, D. H. Zhang, and Y. S. Zhu, Phys. Rev. D 62, 034003 (2000); R. L. Yang, R. G. Ping, and H. Chen, Chin. Phys. Lett. 31, 061301 (2014)

    work page 2000

  51. [51]

    R. G. Ping, Chin. Phys. C 38, 083001 (2014)

    work page 2014

  52. [52]

    Zhong, R

    B. Zhong, R. G. Ping, and Z. J. Xiao, Chin. Phys. C 32, 692 (2008)

    work page 2008

  53. [53]

    Xu et al., Chin

    M. Xu et al., Chin. Phys. C 33, 428 (2009)

    work page 2009

  54. [54]

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

    work page 2021

  55. [55]

    S. J. Brodsky and G. R. Farrar, Phys. Rev. Lett. 31, 1153 (1973)

    work page 1973

  56. [56]

    Perotti, G

    E. Perotti, G. F¨ aldt, A. Kupsc, S. Leupold, and J. J. Song, Phys. Rev. D 99, 056008 (2019)

    work page 2019