Open Access

Improved measurement of $η^{'} \to e^{+} e^{-} ω$

M. Ablikim ¹, M. N. Achasov ^4,d, P. Adlarson ⁸³, X. C. Ai ⁸⁹, C. S. Akondi ^31a,31b, R. Aliberti ³⁹, A. Amoroso ^82a,82c, Q. An^79,65,a, Y. H. An ⁸⁹ et al. (BESIII Collaboration)

Y. H. An ⁸⁹, Y. Bai ⁶³, O. Bakina ⁴⁰, H. R. Bao ⁷¹, X. L. Bao ⁵⁰, M. Barbagiovanni ^82c, V. Batozskaya ^1,49, K. Begzsuren³⁵, N. Berger ³⁹, M. Berlowski ⁴⁹, M. B. Bertani ^30a, D. Bettoni ^31a, F. Bianchi ^82a,82c, E. Bianco^82a,82c, A. Bortone ^82a,82c, I. Boyko ⁴⁰, R. A. Briere ⁵, A. Brueggemann ⁷⁶, D. Cabiati ^82a,82c, H. Cai ⁸⁴, M. H. Cai ^42,l,m, X. Cai ^1,65, A. Calcaterra ^30a, G. F. Cao ^1,71, N. Cao ^1,71, S. A. Cetin ^69a, X. Y. Chai ^51,i, J. F. Chang ^1,65, T. T. Chang ⁴⁸, G. R. Che ⁴⁸, Y. Z. Che ^1,65,71, C. H. Chen ¹⁰, Chao Chen ¹, G. Chen ¹, H. S. Chen ^1,71, H. Y. Chen ²⁰, M. L. Chen ^1,65,71, S. J. Chen ⁴⁷, S. M. Chen ⁶⁸, T. Chen ^1,71, W. Chen ⁵⁰, X. R. Chen ^34,71, X. T. Chen ^1,71, X. Y. Chen ^12,h, Y. B. Chen ^1,65, Y. Q. Chen ¹⁶, Z. K. Chen ⁶⁶, J. Cheng ⁵⁰, L. N. Cheng ⁴⁸, S. K. Choi ¹¹, X. Chu ^12,h, G. Cibinetto ^31a, F. Cossio ^82c, J. Cottee-Meldrum ⁷⁰, H. L. Dai ^1,65, J. P. Dai ⁸⁷, X. C. Dai ⁶⁸, A. Dbeyssi¹⁹, R. E. de Boer ³, D. Dedovich ⁴⁰, C. Q. Deng ⁸⁰, Z. Y. Deng ¹, A. Denig ³⁹, I. Denisenko ⁴⁰, M. Destefanis ^82a,82c, F. De Mori ^82a,82c, E. Di Fiore ^31a,31b, X. X. Ding ^51,i, Y. Ding ⁴⁴, Y. X. Ding ³², Yi. Ding ³⁸, J. Dong ^1,65, L. Y. Dong ^1,71, M. Y. Dong ^1,65,71, X. Dong ⁸⁴, Z. J. Dong ⁶⁶, M. C. Du ¹, S. X. Du ⁸⁹, Shaoxu Du ^12,h, X. L. Du ^12,h, Y. Q. Du ⁸⁴, Y. Y. Duan ⁶¹, Z. H. Duan ⁴⁷, P. Egorov ^40,b, G. F. Fan ⁴⁷, J. J. Fan ²⁰, Y. H. Fan ⁵⁰, J. Fang ^1,65, Jin Fang ⁶⁶, S. S. Fang ^1,71, W. X. Fang ¹, Y. Q. Fang ^1,65,a, L. Fava ^82b,82c, F. Feldbauer ³, G. Felici ^30a, C. Q. Feng ^79,65, J. H. Feng ¹⁶, L. Feng ^42,l,m, Q. X. Feng ^42,l,m, Y. T. Feng ^79,65, M. Fritsch ³, C. D. Fu ¹, J. L. Fu ⁷¹, Y. W. Fu ^1,71, H. Gao ⁷¹, Xu Gao ³⁸, Y. Gao ^79,65, Y. N. Gao ^51,i, Y. Y. Gao ³², Yunong Gao ²⁰, Z. Gao ⁴⁸, S. Garbolino ^82c, I. Garzia ^31a,31b, L. Ge ⁶³, P. T. Ge ²⁰, Z. W. Ge ⁴⁷, C. Geng ⁶⁶, E. M. Gersabeck ⁷⁵, A. Gilman ⁷⁷, K. Goetzen ¹³, J. Gollub ³, J. B. Gong ^1,71, J. D. Gong ³⁸, L. Gong ⁴⁴, W. X. Gong ^1,65, W. Gradl ³⁹, S. Gramigna ^31a,31b, M. Greco ^82a,82c, M. D. Gu ⁵⁶, M. H. Gu ^1,65, C. Y. Guan ^1,71, A. Q. Guo ³⁴, H. Guo ⁵⁵, J. N. Guo ^12,h, L. B. Guo ⁴⁶, M. J. Guo ⁵⁵, R. P. Guo ⁵⁴, X. Guo ⁵⁵, Y. P. Guo ^12,h, Z. Guo ^79,65, A. Guskov ^40,b, J. Gutierrez ²⁹, J. Y. Han ^79,65, T. T. Han ¹, X. Han ^79,65, F. Hanisch ³, K. D. Hao ^79,65, X. Q. Hao ²⁰, F. A. Harris ⁷², C. Z. He ^51,i, K. K. He ^17,47, K. L. He ^1,71, F. H. Heinsius ³, C. H. Heinz ³⁹, Y. K. Heng ^1,65,71, C. Herold ⁶⁷, P. C. Hong ³⁸, G. Y. Hou ^1,71, X. T. Hou ^1,71, Y. R. Hou ⁷¹, Z. L. Hou ¹, H. M. Hu ^1,71, J. F. Hu ^62,k, Q. P. Hu ^79,65, S. L. Hu ^12,h, T. Hu ^1,65,71, Y. Hu ¹, Y. X. Hu ⁸⁴, Z. M. Hu ⁶⁶, G. S. Huang ^79,65, K. X. Huang ⁶⁶, L. Q. Huang ^34,71, P. Huang ⁴⁷, X. T. Huang ⁵⁵, Y. P. Huang ¹, Y. S. Huang ⁶⁶, T. Hussain ⁸¹, N. Hüsken ³⁹, N. in der Wiesche ⁷⁶, J. Jackson ²⁹, Q. Ji ¹, Q. P. Ji ²⁰, W. Ji ^1,71, X. B. Ji ^1,71, X. L. Ji ^1,65, Y. Y. Ji ¹, L. K. Jia ⁷¹, X. Q. Jia ⁵⁵, D. Jiang ^1,71, H. B. Jiang ⁸⁴, S. J. Jiang ¹⁰, X. S. Jiang ^1,65,71, Y. Jiang ⁷¹, J. B. Jiao ⁵⁵, J. K. Jiao ³⁸, Z. Jiao ²⁵, L. C. L. Jin ¹, S. Jin ⁴⁷, Y. Jin ⁷³, M. Q. Jing ⁵⁶, X. M. Jing ⁷¹, T. Johansson ⁸³, S. Kabana ³⁶, X. L. Kang ¹⁰, X. S. Kang ⁴⁴, B. C. Ke ⁸⁹, V. Khachatryan ²⁹, A. Khoukaz ⁷⁶, O. B. Kolcu ^69a, B. Kopf ³, L. Kröger ⁷⁶, L. Krümmel³, Y. Y. Kuang ⁸⁰, M. Kuessner ³, X. Kui ^1,71, N. Kumar ²⁸, A. Kupsc ^49,83, W. Kühn ⁴¹, Q. Lan ⁸⁰, W. N. Lan ²⁰, T. T. Lei ^79,65, M. Lellmann ³⁹, T. Lenz ³⁹, C. Li ⁵², C. H. Li ⁴⁶, C. K. Li ⁴⁸, Chunkai Li ²¹, Cong Li ⁴⁸, D. M. Li ⁸⁹, F. Li ^1,65, G. Li ¹, H. B. Li ^1,71, H. J. Li ²⁰, H. L. Li ⁸⁹, H. N. Li ^62,k, H. P. Li ⁴⁸, Hui Li ⁴⁸, J. N. Li ³², J. S. Li ⁶⁶, J. W. Li ⁵⁵, K. Li ¹, K. L. Li ^42,l,m, L. J. Li ^1,71, L. K. Li ²⁶, Lei Li ⁵³, M. H. Li ⁴⁸, M. R. Li ^1,71, M. T. Li ⁵⁵, P. L. Li ⁷¹, P. R. Li ^42,l,m, Q. M. Li ^1,71, Q. X. Li ⁵⁵, R. Li ^18,34, S. Li ⁸⁹, S. X. Li ⁸⁹, S. Y. Li ⁸⁹, Shanshan Li ^27,j, T. Li ⁵⁵, T. Y. Li ⁴⁸, W. D. Li ^1,71, W. G. Li ^1,a, X. Li ^1,71, X. H. Li ^79,65, X. K. Li ^51,i, X. L. Li ⁵⁵, X. Y. Li ^1,9, X. Z. Li ⁶⁶, Y. Li ²⁰, Y. H. Li ⁴⁸, Y. B. Li ⁸⁵, Y. C. Li ⁶⁶, Y. G. Li ⁷¹, Y. P. Li ³⁸, Z. H. Li ⁴², Z. J. Li ⁶⁶, Z. L. Li ⁸⁹, Z. X. Li ⁴⁸, Z. Y. Li ⁸⁷, C. Liang ⁴⁷, H. Liang ^79,65, Y. F. Liang ⁶⁰, Y. T. Liang ^34,71, Z. Z. Liang ⁶⁶, G. R. Liao ¹⁴, L. B. Liao ⁶⁶, M. H. Liao ⁶⁶, Y. P. Liao ^1,71, J. Libby ²⁸, A. Limphirat ⁶⁷, C. C. Lin ⁶¹, C. X. Lin ³⁴, D. X. Lin ^34,71, T. Lin ¹, B. J. Liu ¹, B. X. Liu ⁸⁴, C. Liu ³⁸, C. X. Liu ¹, F. Liu ¹, F. H. Liu ⁵⁹, Feng Liu ⁶, G. M. Liu ^62,k, H. Liu ^42,l,m, H. B. Liu ¹⁵, H. M. Liu ^1,71, Huihui Liu ²², J. B. Liu ^79,65, J. J. Liu ²¹, K. Liu ^42,l,m, K. Y. Liu ^43,44, Ke Liu ²³, Kun Liu ⁸⁰, L. Liu ⁴², L. C. Liu ⁴⁸, Lu Liu ⁴⁸, M. H. Liu ³⁸, P. L. Liu ⁵⁵, Q. Liu ⁷¹, S. B. Liu ^79,65, T. Liu ¹, W. M. Liu ^79,65, W. T. Liu ⁴³, X. Liu ^42,l,m, X. K. Liu ^42,l,m, X. L. Liu ^12,h, X. P. Liu ^12,h, X. T. Liu ²¹, X. Y. Liu ⁸⁴, Y. Liu ^42,l,m, Y. B. Liu ⁴⁸, Yi Liu ⁸⁹, Z. A. Liu ^1,65,71, Z. D. Liu ⁸⁵, Z. L. Liu ⁸⁰, Z. Q. Liu ⁵⁵, Z. X. Liu ¹, Z. Y. Liu ⁴², X. C. Lou ^1,65,71, H. J. Lu ²⁵, J. G. Lu ^1,65, X. L. Lu ¹⁶, Y. Lu ⁷, Y. H. Lu ^1,71, Y. P. Lu ^1,65, Z. H. Lu ^1,71, C. L. Luo ⁴⁶, J. R. Luo ⁶⁶, J. S. Luo ^1,71, M. X. Luo⁸⁸, T. Luo ^12,h, X. L. Luo ^1,65, Z. Y. Lv ²³, X. R. Lyu ^71,p, Y. F. Lyu ⁴⁸, Y. H. Lyu ⁸⁹, F. C. Ma ⁴⁴, H. L. Ma ¹, Heng Ma ^27,j, J. L. Ma ^1,71, L. L. Ma ⁵⁵, L. R. Ma ⁷³, Q. M. Ma ¹, R. Q. Ma ^1,71, R. Y. Ma ²⁰, T. Ma ^79,65, X. T. Ma ^1,71, X. Y. Ma ^1,65, Y. M. Ma ³⁴, F. E. Maas ¹⁹, I. MacKay ⁷⁷, M. Maggiora ^82a,82c, S. Maity ³⁴, S. Malde ⁷⁷, Q. A. Malik ⁸¹, H. X. Mao ^42,l,m, Y. J. Mao ^51,i, Z. P. Mao ¹, S. Marcello ^82a,82c, A. Marshall ⁷⁰, F. M. Melendi ^31a,31b, Y. H. Meng ⁷¹, Z. X. Meng ⁷³, G. Mezzadri ^31a, H. Miao ^1,71, T. J. Min ⁴⁷, R. E. Mitchell ²⁹, X. H. Mo ^1,65,71, B. Moses ²⁹, N. Yu. Muchnoi ^4,d, J. Muskalla ³⁹, Y. Nefedov ⁴⁰, F. Nerling ^19,f, H. Neuwirth ⁷⁶, Z. Ning ^1,65, S. Nisar ³³, Q. L. Niu ^42,l,m, W. D. Niu ^12,h, Y. Niu ⁵⁵, C. Normand ⁷⁰, S. L. Olsen ^11,71, Q. Ouyang ^1,65,71, I. V. Ovtin ⁴, S. Pacetti ^30b,30c, Y. Pan ⁶³, A. Pathak ¹¹, Y. P. Pei ^79,65, M. Pelizaeus ³, G. L. Peng ^79,65, H. P. Peng ^79,65, X. J. Peng ^42,l,m, Y. Y. Peng ^42,l,m, K. Peters ^13,f, K. Petridis ⁷⁰, J. L. Ping ⁴⁶, R. G. Ping ^1,71, S. Plura ³⁹, V. Prasad ³⁸, L. Pöpping ³, F. Z. Qi ¹, H. R. Qi ⁶⁸, M. Qi ⁴⁷, S. Qian ^1,65, W. B. Qian ⁷¹, C. F. Qiao ⁷¹, J. H. Qiao ²⁰, J. J. Qin ⁸⁰, J. L. Qin ⁶¹, L. Q. Qin ¹⁴, L. Y. Qin ^79,65, P. B. Qin ⁸⁰, X. P. Qin ⁴³, X. S. Qin ⁵⁵, Z. H. Qin ^1,65, J. F. Qiu ¹, Z. H. Qu ⁸⁰, J. Rademacker ⁷⁰, K. Ravindran ⁷⁴, C. F. Redmer ³⁹, A. Rivetti ^82c, M. Rolo ^82c, G. Rong ^1,71, S. S. Rong ^1,71, F. Rosini ^30b,30c, Ch. Rosner ¹⁹, M. Q. Ruan ^1,65, N. Salone ^49,r, A. Sarantsev ^40,e, Y. Schelhaas ³⁹, M. Schernau ³⁶, K. Schoenning ⁸³, M. Scodeggio ^31a, W. Shan ²⁶, X. Y. Shan ^79,65, Z. J. Shang ^42,l,m, J. F. Shangguan ¹⁷, L. G. Shao ^1,71, M. Shao ^79,65, C. P. Shen ^12,h, H. F. Shen ^1,9, W. H. Shen ⁷¹, X. Y. Shen ^1,71, B. A. Shi ⁷¹, Ch. Y. Shi ^87,c, H. Shi ^79,65, J. L. Shi ^8,q, J. Y. Shi ¹, M. H. Shi ⁸⁹, S. Y. Shi ⁸⁰, X. Shi ^1,65, H. L. Song ^79,65, J. J. Song ²⁰, M. H. Song ⁴², T. Z. Song ⁶⁶, W. M. Song ³⁸, Y. X. Song ^51,i,n, Zirong Song ^27,j, S. Sosio ^82a,82c, S. Spataro ^82a,82c, S. Stansilaus ⁷⁷, F. Stieler ³⁹, M. Stolte ³, S. S Su ⁴⁴, G. B. Sun ⁸⁴, G. X. Sun ¹, H. Sun ⁷¹, H. K. Sun ¹, J. F. Sun ²⁰, K. Sun ⁶⁸, L. Sun ⁸⁴, R. Sun ⁷⁹, S. S. Sun ^1,71, T. Sun ^57,g, W. Y. Sun ⁵⁶, Y. C. Sun ⁸⁴, Y. H. Sun ³², Y. J. Sun ^79,65, Y. Z. Sun ¹, Z. Q. Sun ^1,71, Z. T. Sun ⁵⁵, H. Tabaharizato ¹, C. J. Tang⁶⁰, G. Y. Tang ¹, J. Tang ⁶⁶, J. J. Tang ^79,65, L. F. Tang ⁴³, Y. A. Tang ⁸⁴, Z. H. Tang ^1,71, L. Y. Tao ⁸⁰, M. Tat ⁷⁷, J. X. Teng ^79,65, J. Y. Tian ^79,65, W. H. Tian ⁶⁶, Y. Tian ³⁴, Z. F. Tian ⁸⁴, K. Yu. Todyshev ⁴, I. Uman ^69b, E. van der Smagt ³, B. Wang ⁶⁶, Bin Wang ¹, Bo Wang ^79,65, C. Wang ^42,l,m, Chao Wang ²⁰, Cong Wang ²³, D. Y. Wang ^51,i, F. K. Wang ⁶⁶, H. J. Wang ^42,l,m, H. R. Wang ⁸⁶, J. Wang ¹⁰, J. J. Wang ⁸⁴, J. P. Wang ³⁷, K. Wang ^1,65, L. L. Wang ¹, L. W. Wang ³⁸, M. Wang ⁵⁵, Mi Wang ^79,65, N. Y. Wang ⁷¹, P. Wang ²¹, S. Wang ^42,l,m, Shun Wang ⁶⁴, T. Wang ^12,h, W. Wang ⁶⁶, W. P. Wang ³⁹, X. F. Wang ^42,l,m, X. L. Wang ^12,h, X. N. Wang ^1,71, Xin Wang ^27,j, Y. Wang ¹, Y. D. Wang ⁵⁰, Y. F. Wang ^1,9,71, Y. H. Wang ^42,l,m, Y. J. Wang ^79,65, Y. L. Wang ²⁰, Y. N. Wang ⁵⁰, Yanning Wang ⁸⁴, Yaqian Wang ¹⁸, Yi Wang ⁶⁸, Yuan Wang ^18,34, Z. Wang ^1,65, Z. L. Wang ², Z. Q. Wang ^12,h, Z. Y. Wang ^1,71, Zhi Wang ⁴⁸, Ziyi Wang ⁷¹, D. Wei ⁴⁸, D. H. Wei ¹⁴, D. J. Wei ⁷³, H. R. Wei ⁴⁸, F. Weidner ⁷⁶, H. R. Wen ³⁴, S. P. Wen ¹, U. Wiedner ³, G. Wilkinson ⁷⁷, M. Wolke⁸³, J. F. Wu ^1,9, L. H. Wu ¹, L. J. Wu ²⁰, Lianjie Wu ²⁰, S. G. Wu ^1,71, S. M. Wu ⁷¹, X. W. Wu ⁸⁰, Z. Wu ^1,65, H. L. Xia ^79,65, L. Xia ^79,65, B. H. Xiang ^1,71, D. Xiao ^42,l,m, G. Y. Xiao ⁴⁷, H. Xiao ⁸⁰, Y. L. Xiao ^12,h, Z. J. Xiao ⁴⁶, C. Xie ⁴⁷, K. J. Xie ^1,71, Y. Xie ⁵⁵, Y. G. Xie ^1,65, Y. H. Xie ⁶, Z. P. Xie ^79,65, T. Y. Xing ^1,71, D. B. Xiong ¹, G. F. Xu ¹, H. Y. Xu ², Q. J. Xu ¹⁷, Q. N. Xu ³², T. D. Xu ⁸⁰, X. P. Xu ⁶¹, Y. Xu ^12,h, Y. C. Xu ⁸⁶, Z. S. Xu ⁷¹, F. Yan ²⁴, L. Yan ^12,h, W. B. Yan ^79,65, W. C. Yan ⁸⁹, W. H. Yan ⁶, W. P. Yan ²⁰, X. Q. Yan ^12,h, Y. Y. Yan ⁶⁷, H. J. Yang ^57,g, H. L. Yang ³⁸, H. X. Yang ¹, J. H. Yang ⁴⁷, R. J. Yang ²⁰, X. Y. Yang ⁷³, Y. Yang ^12,h, Y. G. Yang ⁵⁶, Y. H. Yang ⁴⁸, Y. M. Yang ⁸⁹, Y. Q. Yang ¹⁰, Y. Z. Yang ²⁰, Youhua Yang ⁴⁷, Z. Y. Yang ⁸⁰, W. J. Yao ⁶, Z. P. Yao ⁵⁵, M. Ye ^1,65, M. H. Ye ^9,a, Z. J. Ye ^62,k, K. Yi ⁴⁶, Junhao Yin ⁴⁸, Z. Y. You ⁶⁶, B. X. Yu ^1,65,71, C. X. Yu ⁴⁸, G. Yu ¹³, J. S. Yu ^27,j, L. W. Yu ^12,h, T. Yu ⁸⁰, X. D. Yu ^51,i, Y. C. Yu ⁸⁹, Yongchao Yu ⁴², C. Z. Yuan ^1,71, H. Yuan ^1,71, J. Yuan ³⁸, Jie Yuan ⁵⁰, L. Yuan ², M. K. Yuan ^12,h, S. H. Yuan ⁸⁰, Y. Yuan ^1,71, C. X. Yue ⁴³, Ying Yue ²⁰, A. A. Zafar ⁸¹, F. R. Zeng ⁵⁵, S. H. Zeng ⁷⁰, X. Zeng ^12,h, Y. J. Zeng ^1,71, Yujie Zeng ⁶⁶, Y. C. Zhai ⁵⁵, Y. H. Zhan ⁶⁶, B. L. Zhang ^1,71, B. X. Zhang ^1,a, D. H. Zhang ⁴⁸, G. Y. Zhang ²⁰, Gengyuan Zhang ^1,71, H. Zhang ^79,65, H. C. Zhang ^1,65,71, H. H. Zhang ⁶⁶, H. Q. Zhang ^1,65,71, H. R. Zhang ^79,65, H. Y. Zhang ^1,65, Han Zhang ⁸⁹, J. Zhang ⁶⁶, J. J. Zhang ⁵⁸, J. L. Zhang ²¹, J. Q. Zhang ⁴⁶, J. S. Zhang ^12,h, J. W. Zhang ^1,65,71, J. X. Zhang ^42,l,m, J. Y. Zhang ¹, J. Z. Zhang ^1,71, Jianyu Zhang ⁷¹, Jin Zhang ⁵³, Jiyuan Zhang ^12,h, L. M. Zhang ⁶⁸, Lei Zhang ⁴⁷, N. Zhang ³⁸, P. Zhang ^1,9, Q. Zhang ²⁰, Q. Y. Zhang ³⁸, Q. Z. Zhang ⁷¹, R. Y. Zhang ^42,l,m, S. H. Zhang ^1,71, S. N. Zhang ⁷⁷, Shulei Zhang ^27,j, X. M. Zhang ¹, X. Y. Zhang ⁵⁵, Y. T. Zhang ⁸⁹, Y. H. Zhang ^1,65, Y. P. Zhang ^79,65, Yao Zhang ¹, Yu Zhang ⁸⁰, Yu Zhang ⁶⁶, Z. Zhang ³⁴, Z. D. Zhang ¹, Z. H. Zhang ¹, Z. L. Zhang ³⁸, Z. X. Zhang ²⁰, Z. Y. Zhang ⁸⁴, Zh. Zh. Zhang ²⁰, Zhilong Zhang ⁶¹, Ziyang Zhang ⁵⁰, Ziyu Zhang ⁴⁸, G. Zhao ¹, J.-P. Zhao ⁷¹, J. Y. Zhao ^1,71, J. Z. Zhao ^1,65, L. Zhao ¹, Lei Zhao ^79,65, M. G. Zhao ⁴⁸, R. P. Zhao ⁷¹, S. J. Zhao ⁸⁹, Y. B. Zhao ^1,65, Y. L. Zhao ⁶¹, Y. P. Zhao ⁵⁰, Y. X. Zhao ^34,71, Z. G. Zhao ^79,65, A. Zhemchugov ^40,b, B. Zheng ⁸⁰, B. M. Zheng ³⁸, J. P. Zheng ^1,65, W. J. Zheng ^1,71, W. Q. Zheng ¹⁰, X. R. Zheng ²⁰, Y. H. Zheng ^71,p, B. Zhong ⁴⁶, C. Zhong ²⁰, X. Zhong ⁴⁵, H. Zhou ^39,55,o, J. Q. Zhou ³⁸, S. Zhou ⁶, X. Zhou ⁸⁴, X. K. Zhou ⁶, X. R. Zhou ^79,65, X. Y. Zhou ⁴³, Y. X. Zhou ⁸⁶, Y. Z. Zhou ²⁰, A. N. Zhu ⁷¹, J. Zhu ⁴⁸, K. Zhu ¹, K. J. Zhu ^1,65,71, K. S. Zhu ^12,h, L. X. Zhu ⁷¹, Lin Zhu ²⁰, S. H. Zhu ⁷⁸, T. J. Zhu ^12,h, W. D. Zhu ^12,h, W. J. Zhu ¹, W. Z. Zhu ²⁰, Y. C. Zhu ^79,65, Z. A. Zhu ^1,71, X. Y. Zhuang ⁴⁸, M. Zhuge ⁵⁵, J. H. Zou ¹, and J. Zu ³⁴ (BESIII Collaboration)

¹Institute of High Energy Physics, Beijing 100049, People’s Republic of China
²Beihang University, Beijing 100191, People’s Republic of China
³Bochum Ruhr-University, D-44780 Bochum, Germany
⁴Budker Institute of Nuclear Physics SB RAS (BINP), Novosibirsk 630090, Russia
⁵Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
⁶Central China Normal University, Wuhan 430079, People’s Republic of China
⁷Central South University, Changsha 410083, People’s Republic of China
⁸Chengdu University of Technology, Chengdu 610059, People’s Republic of China
⁹China Center of Advanced Science and Technology, Beijing 100190, People’s Republic of China
¹⁰China University of Geosciences, Wuhan 430074, People’s Republic of China
¹¹Chung-Ang University, Seoul, 06974, Republic of Korea
¹²Fudan University, Shanghai 200433, People’s Republic of China
¹³GSI Helmholtzcentre for Heavy Ion Research GmbH, D-64291 Darmstadt, Germany
¹⁴Guangxi Normal University, Guilin 541004, People’s Republic of China
¹⁵Guangxi University, Nanning 530004, People’s Republic of China
¹⁶Guangxi University of Science and Technology, Liuzhou 545006, People’s Republic of China
¹⁷Hangzhou Normal University, Hangzhou 310036, People’s Republic of China
¹⁸Hebei University, Baoding 071002, People’s Republic of China
¹⁹Helmholtz Institute Mainz, Staudinger Weg 18, D-55099 Mainz, Germany
²⁰Henan Normal University, Xinxiang 453007, People’s Republic of China
²¹Henan University, Kaifeng 475004, People’s Republic of China
²²Henan University of Science and Technology, Luoyang 471003, People’s Republic of China
²³Henan University of Technology, Zhengzhou 450001, People’s Republic of China
²⁴Hengyang Normal University, Hengyang 421001, People’s Republic of China
²⁵Huangshan College, Huangshan 245000, People’s Republic of China
²⁶Hunan Normal University, Changsha 410081, People’s Republic of China
²⁷Hunan University, Changsha 410082, People’s Republic of China
²⁸Indian Institute of Technology Madras, Chennai 600036, India
²⁹Indiana University, Bloomington, Indiana 47405, USA
^30aINFN Laboratori Nazionali di Frascati, INFN Laboratori Nazionali di Frascati, I-00044, Frascati, Italy
^30bINFN Sezione di Perugia, I-06100, Perugia, Italy
^30cUniversity of Perugia, I-06100, Perugia, Italy
^31aINFN Sezione di Ferrara, INFN Sezione di Ferrara, I-44122, Ferrara, Italy
^31bUniversity of Ferrara, I-44122, Ferrara, Italy
³²Inner Mongolia University, Hohhot 010021, People’s Republic of China
³³Institute of Business Administration, University Road, Karachi, 75270 Pakistan
³⁴Institute of Modern Physics, Lanzhou 730000, People’s Republic of China
³⁵Institute of Physics and Technology, Mongolian Academy of Sciences, Peace Avenue 54B, Ulaanbaatar 13330, Mongolia
³⁶Instituto de Alta Investigación, Universidad de Tarapacá, Casilla 7D, Arica 1000000, Chile
³⁷Jiangsu Ocean University, Lianyungang 222000, People’s Republic of China
³⁸Jilin University, Changchun 130012, People’s Republic of China
³⁹Johannes Gutenberg University of Mainz, Johann-Joachim-Becher-Weg 45, D-55099 Mainz, Germany
⁴⁰Joint Institute for Nuclear Research, 141980 Dubna, Moscow region, Russia
⁴¹Justus-Liebig-Universitaet Giessen, II. Physikalisches Institut, Heinrich-Buff-Ring 16, D-35392 Giessen, Germany
⁴²Lanzhou University, Lanzhou 730000, People’s Republic of China
⁴³Liaoning Normal University, Dalian 116029, People’s Republic of China
⁴⁴Liaoning University, Shenyang 110036, People’s Republic of China
⁴⁵Longyan University, Longyan 364000, People’s Republic of China
⁴⁶Nanjing Normal University, Nanjing 210023, People’s Republic of China
⁴⁷Nanjing University, Nanjing 210093, People’s Republic of China
⁴⁸Nankai University, Tianjin 300071, People’s Republic of China
⁴⁹National Centre for Nuclear Research, Warsaw 02-093, Poland
⁵⁰North China Electric Power University, Beijing 102206, People’s Republic of China
⁵¹Peking University, Beijing 100871, People’s Republic of China
⁵²Qufu Normal University, Qufu 273165, People’s Republic of China
⁵³Renmin University of China, Beijing 100872, People’s Republic of China
⁵⁴Shandong Normal University, Jinan 250014, People’s Republic of China
⁵⁵Shandong University, Jinan 250100, People’s Republic of China
⁵⁶Shandong University of Technology, Zibo 255000, People’s Republic of China
⁵⁷Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
⁵⁸Shanxi Normal University, Linfen 041004, People’s Republic of China
⁵⁹Shanxi University, Taiyuan 030006, People’s Republic of China
⁶⁰Sichuan University, Chengdu 610064, People’s Republic of China
⁶¹Soochow University, Suzhou 215006, People’s Republic of China
⁶²South China Normal University, Guangzhou 510006, People’s Republic of China
⁶³Southeast University, Nanjing 211100, People’s Republic of China
⁶⁴Southwest University of Science and Technology, Mianyang 621010, People’s Republic of China
⁶⁵State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People’s Republic of China
⁶⁶Sun Yat-Sen University, Guangzhou 510275, People’s Republic of China
⁶⁷Suranaree University of Technology, University Avenue 111, Nakhon Ratchasima 30000, Thailand
⁶⁸Tsinghua University, Beijing 100084, People’s Republic of China
^69aTurkish Accelerator Center Particle Factory Group, Istinye University, 34010, Istanbul, Turkey
^69bNear East University, Nicosia, North Cyprus, 99138, Mersin 10, Turkey
⁷⁰University of Bristol, H H Wills Physics Laboratory, Tyndall Avenue, Bristol, BS8 1TL, United Kingdom
⁷¹University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
⁷²University of Hawaii, Honolulu, Hawaii 96822, USA
⁷³University of Jinan, Jinan 250022, People’s Republic of China
⁷⁴University of La Serena, Av. Raúl Bitrán 1305, La Serena, Chile
⁷⁵University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
⁷⁶University of Muenster, Wilhelm-Klemm-Strasse 9, 48149 Muenster, Germany
⁷⁷University of Oxford, Keble Road, Oxford OX13RH, United Kingdom
⁷⁸University of Science and Technology Liaoning, Anshan 114051, People’s Republic of China
⁷⁹University of Science and Technology of China, Hefei 230026, People’s Republic of China
⁸⁰University of South China, Hengyang 421001, People’s Republic of China
⁸¹University of the Punjab, Lahore-54590, Pakistan
^82aUniversity of Turin and INFN, University of Turin, I-10125, Turin, Italy
^82bUniversity of Eastern Piedmont, I-15121, Alessandria, Italy
^82cINFN, I-10125, Turin, Italy
⁸³Uppsala University, Box 516, SE-75120 Uppsala, Sweden
⁸⁴Wuhan University, Wuhan 430072, People’s Republic of China
⁸⁵Xi’an Jiaotong University, No.28 Xianning West Road, Xi’an, Shaanxi 710049, People’s Republic of China
⁸⁶Yantai University, Yantai 264005, People’s Republic of China
⁸⁷Yunnan University, Kunming 650500, People’s Republic of China
⁸⁸Zhejiang University, Hangzhou 310027, People’s Republic of China
⁸⁹Zhengzhou University, Zhengzhou 450001, People’s Republic of China

^*Full author list given at the end of the article.
^aDeceased.
^bAlso at the Moscow Institute of Physics and Technology, Moscow 141700, Russia.
^cAlso at the Functional Electronics Laboratory, Tomsk State University, Tomsk, 634050, Russia.
^dAlso at the Novosibirsk State University, Novosibirsk, 630090, Russia.
^eAlso at the NRC “Kurchatov Institute,” PNPI, 188300, Gatchina, Russia.
^fAlso at Goethe University Frankfurt, 60323 Frankfurt am Main, Germany.
^gAlso at Key Laboratory for Particle Physics, Astrophysics and Cosmology, Ministry of Education; Shanghai Key Laboratory for Particle Physics and Cosmology; Institute of Nuclear and Particle Physics, Shanghai 200240, People’s Republic of China.
^hAlso at Key Laboratory of Nuclear Physics and Ion-beam Application (MOE) and Institute of Modern Physics, Fudan University, Shanghai 200443, People’s Republic of China.
ⁱAlso at State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, People’s Republic of China.
^jAlso at School of Physics and Electronics, Hunan University, Changsha 410082, China.
^kAlso at Guangdong Provincial Key Laboratory of Nuclear Science, Institute of Quantum Matter, South China Normal University, Guangzhou 510006, China.
^lAlso at MOE Frontiers Science Center for Rare Isotopes, Lanzhou University, Lanzhou 730000, People’s Republic of China.
^mAlso at Lanzhou Center for Theoretical Physics, Lanzhou University, Lanzhou 730000, People’s Republic of China.
ⁿAlso at Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
^oAlso at Helmholtz Institute Mainz, Staudinger Weg 18, D-55099 Mainz, Germany.
^pAlso at Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China.
^qAlso at Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province, Chengdu University of Technology, Chengdu 610059, People’s Republic of China.
^rCurrently at University of Silesia in Katowice, Institute of Physics, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland.

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Phys. Rev. D 114, 012017 – Published 23 July, 2026

DOI: https://doi.org/10.1103/qdl2-7ltt

Abstract

Using a sample of $(10087 \pm 44) \times 10^{6} J / ψ$ events collected with the BESIII detector, an improved measurement of the decay $η^{'} \to e^{+} e^{-} ω$ , with $ω \to π^{+} π^{-} π^{0}$ and $π^{0} \to γ γ$ is performed. The branching fraction is determined to be $B (η^{'} \to e^{+} e^{-} ω) = (1.79 \pm 0.09 \pm 0.12) \times 10^{- 4}$ , where the first uncertainty is statistical and the second is systematic. This result is consistent with the previous measurement and is obtained with significantly improved precision. Furthermore, the first measurement of the transition form factor cutoff parameter for this decay is reported, with $Λ^{- 1} = (2.92 \pm 0.83 \pm 0.15) {GeV}^{- 1}$ . These measurements provide valuable input for understanding the internal structure of the $η^{'}$ meson and testing theoretical models.

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Form factors

Article Text

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Phys. Rev. D 114, 012017– Published 23 July, 2026

Vol. 114, Iss. 1 — 1 July 2026

Received 10 March 2026
Accepted 29 June 2026

DOI: https://doi.org/10.1103/qdl2-7ltt

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

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Improved measurement of $η^{'} \to e^{+} e^{-} ω$