Observation of e(+)e(-)→π(0)π(0)hc and a neutral charmoniumlike structure Zc(4020)(0).

Abstract

Using data collected with the BESIII detector operating at the Beijing Electron Positron Collider at center-of-mass energies of sqrt[s]=4.23, 4.26, and 4.36 GeV, we observe e(+)e(-)→π(0)π(0)hc for the first time. The Born cross sections are measured and found to be about half of those of e(+)e(-)→π(+)π(-)hc within less than 2σ. In the π(0)hc mass spectrum, a structure at 4.02  GeV/c(2) is found. It is most likely to be the neutral isospin partner of the Zc(4020)(±) observed in the process of e(+)e(-)→π(+)π(-)hc being found. A fit to the π(0)hc invariant mass spectrum, with the width of the Zc(4020)(0) fixed to that of its charged isospin partner and possible interferences with non-Zc(4020)(0) amplitudes neglected, gives a mass of (4023.9±2.2±3.8)  MeV/c(2) for the Zc(4020)(0), where the first error is statistical and the second systematic.

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@article{Ablikim2014ObservationOE, title={Observation of e(+)e(-)→π(0)π(0)hc and a neutral charmoniumlike structure Zc(4020)(0).}, author={Melike Ablikim and M . N . Achasov and X. C. Ai and Onur Albayrak and Marcus Albrecht and Divakar Justus Ambrose and Antonio Amoroso and Fengpeng An and Qi An and Jing Bai and R B F Baldini Ferroli and Yoshitsune Ban and David W. Bennett and John V. Bennett and M. B. Bertani and Diego Bettoni and Jian-min Bian and Francesca Bianchi and Elin Boger and Oleg Bondarenko and Igor Boyko and R . A . Briere and H C Cai and X . Z . Cai and Orhan Cakir and Andrea Calcaterra and Gang Cao and S. A. Çetin and J . F . Chang and G . A . Chelkov and Gui-ping Chen and Huan Chen and H . Y . Chen and Joseph Chen and M Chen and S Chen and Xu Chen and Xue Rong Chen and Y Chen and Heping Cheng and X K Chu and Y. Chu and Gianluigi Cibinetto and Dan Cronin-Hennessy and H. L. Dai and Jian Dai and D . V . Dedovich and Zhiting Deng and Achim G. Denig and I B Denysenko and Marco Destefanis and F De Mori and Yang Ding and C Dong and Jun Dong and Lin Dong and M. Dong and S. X. Du and Piaopiao Duan and J. Fan and Jinggui Fang and S Fang and Xiang Fang and Yi Fang and Luciano Fava and F . Feldbauer and G. Felici and Chao Feng and Emiliano Fioravanti and C Fu and Q X Gao and Y. Gao and I . Garzia and Klaus Goetzen and W. X. Gong and Wolfgang Gradl and Massimo Greco and Mai Gu and Yan Gu and Yue Guan and Author Guo and L. Guo and T W Guo and Yue Guo and Z. Haddadi and Annette Hafner and S. H. Han and Y. Han and Frederick A. Harris and Kan Lian He and Zhi He and Theo Held and Yee Kiat Heng and Zhonghuai Hou and Chunhong Hu and H Hu and Jin Hu and Ting Hu and Y Hu and G. M. Huang and G. Steven Huang and He Huang and Justin Huang and X Huang and Yining Huang and Tajdar Hussain and Qingqiang Ji and Xue Ji and Xiangdong Ji and Lisa L Jiang and L Jiang and Xiaoyin Sara Jiang and Jian Jiao and Zhi-jun Jiao and Da Peng Jin and Seong Lim Jin and Tord Johansson and Arttu Julin and Nasser Kalantar-Nayestanaki and Xue Liang Kang and Xiaotao Kang and M . O . Kavatsyuk and B. C. Ke and R . Kliemt and Birgitt Kloss and O. B. Kolcu and B . Kopf and M. Kornicer and William P . Kuehn and Andrzej Kupś{\'c} and Wei Lai and Jens S{\"{o}ren Lange and Manuel Lara and Penny Larin and M . Leyhe and Cheng Li and D. Li and F. Li and Guang Li and L Li and Ji-cheng Li and Jin Li and K Li and Q Li and T Li and W Li and W. Li and Xuemin Li and X. M. Li and X . N . Li and X . Q . Li and Z . B . Li and Hailong Liang and Y. Liang and Y. T. Liang and G. R. Liao and D-c Lin and B Liu and Cheng Chih Liu and Frank Liu and Fang Liu and Feng Liu and H. B. Liu and Helen Liu and H. M. Liu and Jun Liu and J . Y . Liu and Kai Liu and L. Liu and Q Liu and S. Liu and X Liu and Xiang Liu and Yin Liu and Zhiqing Liu and Zhiqiang Liu and Herbert Loehner and Xiaoxia Lou and He Jun Lu and Juan Lu and R. Q. Lu and Y. Lu and Chun Luo and Millore X-M Luo and Tianci Luo and Xuan Luo and Ming Lv and Xujian Lyu and Fu Chan Ma and Hoang L Ma and Qiang Ma and S W Ma and Tammy Ma and Xi nian Ma and Xiaodong Ma and F. E. Maas and Marcello Maggiora and Qaisar A. Malik and Y. Mao and Zhiping Mao and Sandra Marcello and Johan G. Messchendorp and Jin Min and Tai Jin Min and Reginald E. Mitchell and Xiao-yang Mo and Y. J. Mo and Hossein Moeini and C A Morales Morales and Keiichi Moriya and N . Yu . Muchnoi and Hideki Muramatsu and Yu . Nefedov and Frank Nerling and I. B. Nikolaev and Z Ning and Saleha Nisar and Shuangxia Niu and X Y Niu and Sharon L. Olsen and Qi Ouyang and Simone Pacetti and Paola Patteri and M. Pelizaeus and H. Peng and Keith Peters and Jia - Lun Ping and R . - G . Ping and Ron Poling and Yang Pu and Min Qi and Sujuan Qian and Chun Feng Qiao and Li Qin and Ning Qin and Xuezhong Qin and Y Z Qin and Zheng Qin and Jing Qiu and Khalid H. Rashid and Ch . F . Redmer and He Ren and M D Ripka and Guobin Rong and Xiang-yan Ruan and Valdir Santoro and A . V . Sarantsev and M . Savri{\'e} and K . Sch{\"{o}nning and Stefan Schumann and W . L . Shan and Ming'an Shao and C. P. Shen and Peng Shen and Xiao Shen and Huan-yuan Sheng and Matthew R Shepherd and Won Moon Song and X Song and S . Sosio and Stephano Spataro and B . Spruck and Gang Sun and J. Sun and S Sun and Ying Sun and Y. Sun and Zhi Sun and Z. Sun and C. Tang and Xiu Feng Tang and I Tapan and Edward H Thorndike and M . Tiemens and Diana T{\'o}th and Matthias S. Ullrich and Ismail Uman and Gary S. Varner and Belinda Wang and D Wang and D. Y. Wang and K Wang and L. Wang and L Wang and M Wang and Philip L Wang and Q. Wang and S. G. Wang and W Wang and X Wang and Y Wang and Yanping Wang and Zheng Wang and Zhenlong Wang and Zhonghua Wang and David H. Wei and Jun Wei and P Weidenkaff and S Wen and Ulrich Wiedner and Matthias Wolke and Li-Ming Wu and Zhiliang Wu and Liu Xia and Y Xia and Daliao Xiao and Z J Xiao and Yuehong Xie and Q L Xiu and G. F. Xu and L Xu and Qin Jun Xu and Qing Xu and X. Xu and Z N Xue and L Yan and Wen Yan and Wen Chen Yan and Yu Yan and H. X. Yang and Li Yang and Y. Yang and Hong Ye and M. H. Ye and Jian Yin and B Yu and C. Yu and H Yu and J S Yu and Changzheng Yuan and Weiping Yuan and Yi Yuan and A Yuncu and Azhar Ali Zafar and Adriano Zallo and Y Zeng and B. Zhang and Bao Zhang and Cheng Zhang and D Zhang and Hong Hui Zhang and H . T . Zhang and Huiyuan Zhang and J. J. Zhang and J Zhang and Jianyi Zhang and Jason Y. Zhang and Jia Zhang and Kevin Zhang and L Zhang and Shenghui Zhang and X-h Zhang and X Y Zhang and Yingxin Zhang and Z H Zhang and Zhenjun Zhang and Z Zhang and Guiping Zhao and Jingwei Zhao and Jian Zhao and J Z Zhao and Lei Zhao and Ling Zhao and Ming Zhao and Qian Zhao and Shaohua Zhao and Tongbiao Zhao and Y Zhao and Z. Zhao and A . Zhemchugov and Bin Zheng and J. Zheng and Y. Zheng and Baiyu Zhong and Lingli Zhou and Li Zhou and Xian Zhou and X K Zhou and Xue Rui Zhou and K. Zhu and Shu-Hong Zhu and X. L. Zhu and Y. Zhu and Y. S. Zhu and Z. Zhu and Jian Zhuang and Bing-song Zou and Jun Zou}, journal={Physical review letters}, year={2014}, volume={113 21}, pages={212002} }