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Medina Ablikim, Mikhail N. Achasov, Samer Ahmed, O. Albayrak, Malte Albrecht, M. Alekseev, D. J. Ambrose, Antonio Amoroso, Fenfen An, Qi An, Jingzhi Bai, Olga Bakina, Rinaldo Baldini Ferroli, Yong Ban, D. W. Bennett, Jake V. Bennett, Niklaus Berger, Monica Bertani, Diego Bettoni, J. M. Bian, Fabrizio Bianchi, E. Boger, Igor R. Boyko, Roy A. Briere, H. Cai, Xiao Cai, O. Cakir, Alessandro Calcaterra, G. F. Cao, Serkant Ali Çetin, J. Chai, Jinfan Chang, Gueorgui A. Chelkov, G. Chen, Hesheng Chen, J. C. Chen, M. L. Chen, P. L. Chen, S. J. Chen, X. R. Chen, Yuanbo Chen, X. K. Chu, Gianluigi Cibinetto, Hongliang Dai, J. P. Dai, Alaa Dbeyssi, Dmitri V. Dedovich, Ziyan Deng, Achim Denig, Igor Denysenko, Marco Giovanni Maria Destefanis, Francesca De Mori, Y. Ding, C. Dong, J. Dong, Liaoyuan Dong, Mingyi Dong, O. Dorjkhaidav, Z. L. Dou, Shuxian Du, P. F. Duan, J. Fang, Shuangshi Fang, X. Fang, Y. Fang, Riccardo Farinelli, Luciano Fava, S. Fegan, Florian Feldbauer, Giulietto Felici, C. Q. Feng, Elisa Fioravanti, Miriam Fritsch, Chengdong Fu, Y. G. Gao, Q. Gao, X. L. Gao, Y. Gao, Z. Gao, I. Garzia, Klaus Goetzen, L. Gong, Wenxuan Gong, Wolfgang Gradl, M. Greco, Minhao Gu, S. Gu, Y. T. Gu, Aiqiang Guo, L. B. Guo, R. P. Guo, Yuping Guo, Z. Haddadi, A. Hafner, S. Han, Xiqing Hao, F. A. Harris, K. L. He, X. Q. He, Fritz-Herbert Heinsius, T. Held, Yuekun Heng, Tobias Holtmann, Zhilong Hou, C. Hu, Haiming Hu, T. Hu, Y. Hu, G. S. Huang, J. S. Huang, X. T. Huang, X. Z. Huang, Z. L. Huang, Tahir Hussain, Walter Ikegami Andersson, Quan Ji, Qingping Ji, X. B. Ji, X. L. Ji, Xiaoshan Jiang, X. Y. Jiang, J. B. Jiao, Z. Jiao, D. P. Jin, Shan Jin, Tord Johansson, A. Julin, Nasser Kalantar-Nayestanaki, Xiaolin Kang, X. S. Kang, Myroslav O. Kavatsyuk, Bai-Cian Ke, Tabassum Khan, P. Kiese, Ralf Kliemt, B. Kloss, Onur Bugra Kolcu, Bertram Kopf, M. Kornicer, Andrzej Kupsc, Wolfgang Kühn, Jens Sören Lange, M. Lara, Paul Larin, Lia Lavezzi, H. Leithoff, C. Leng, C. Li, Cheng Li, D. M. Li, F. Li, F. Y. Li, G. Li, Haibo Li, H. J. Li, J. C. Li, Jin Li, K. Li, K. Li, Lei Li, P. L. Li, P. R. Li, Q. Y. Li, T. Li, Weidong Li, Weiguo Li, X. L. Li, X. N. Li, X. Q. Li, Z. B. Li, H. Liang, Y. F. Liang, Y. T. Liang, G. R. Liao, D. X. Lin, B. Liu, B. J. Liu, C. X. Liu, D. Liu, Fu-Hu Liu, Fang Liu, Feng Liu, H. B. Liu, H. H. Liu, H. H. Liu, H. M. Liu, J. B. Liu, J. P. Liu, J. Y. Liu, K. Liu, K. Y. Liu, Ke Liu, L. D. Liu, P. L. Liu, Q. Liu, S. B. Liu, X. Liu, Y. B. Liu, Y. Y. Liu, Zhen-An Liu, Zhiqing Liu, H. Loehner, Y. F. Long, Xinchou Lou, H. J. Lu, Junguang Lu, Y. Lu, Yunpeng Lu, Chenglin Luo, M. X. Luo, T. Luo, X. L. Luo, Xiao-Rui Lyu, Fengcai Ma, H. L. Ma, Lianliang Ma, M. M. Ma, Qiumei Ma, T. Ma, X. N. Ma, Xiaoyan Ma, Y. M. Ma, Frank E. Maas, Marco Maggiora, Qadeer Afzal Malik, Yajun Mao, Zepu Mao, Simonetta Marcello, Johannes Gerhardus Messchendorp, Giulio Mezzadri, J. Min, T. J. Min, Ryan Edward Mitchell, Xiaohu Mo, Y. J. Mo, C. Morales Morales, G. Morello, Nikolai Yu. Muchnoi, H. Muramatsu, P. Musiol, Yury Nefedov, Frank Nerling, Ivan Borisovich Nikolaev, Z. Ning, Shabana Nisar, S. L. Niu, X. Y. Niu, Stephen L. Olsen, Qun Ouyang, Simone Pacetti, Y. Pan, P. Patteri, Marc Pelizäus, J. Pellegrino, H. P. Peng, Klaus Peters, J. Pettersson, J. L. Ping, R. G. Ping, Ronald Poling, Vindhyawasini Prasad, H. R. Qi, Ming Qi, S. Qian, Congfeng Qiao, J. J. Qin, N. Qin, X. S. Qin, Zhonghua Qin, Jinfa Qiu, K. H. Rashid, Christoph Florian Redmer, M. Ripka, Gang Rong, Christoph Rosner, X. D. Ruan, Andrei V. Sarantsev, M. Savrié, Claudius Schnier, Karin Schönning, Wei Shan, M. Shao, C. P. Shen, P. X. Shen, X. Y. Shen, H. Y. Sheng, J. J. Song, X. Y. Song, Stefano Sosio, Stefano Spataro, Gongxing Sun, J. F. Sun, S. S. Sun, X. H. Sun, Y. J. Sun, Y. K. Sun, Y. Z. Sun, Z. J. Sun, Z. T. Sun, C. J. Tang, X. Tang, I. Tapan, E. H. Thorndike, M. Tiemens, Ts Tsednee, Ismail Uman, G. S. Varner, B. Wang, B. L. Wang, D. Wang, D. Y. Wang, Dan Wang, K. Wang, L. L. Wang, L. S. Wang, M. Wang, P. Wang, P. L. Wang, W. P. Wang, X. F. Wang, Y. D. Wang, Y. F. Wang, Y. Q. Wang, Z. Wang, Z. G. Wang, Z. H. Wang, Z. Y. Wang, Z. Y. Wang, T. Weber, D. H. Wei, P. Weidenkaff, Shuopin Wen, Ulrich Wiedner, Magnus Wolke, Linghui Wu, L. J. Wu, Z. Wu, L. Xia, Y. Xia, D. Xiao, Y. J. Xiao, Zhenjun Xiao, Y. G. Xie, Yuehong Xie, X. A. Xiong, Q. L. Xiu, Guofa Xu, J. J. Xu, L. Xu, Q. J. Xu, Q. N. Xu, Xinping Xu, L. Yan, W. B. Yan, W. C. Yan, Y. H. Yan, H. J. Yang, Hongxun Yang, L. Yang, Y. H. Yang, Yongxu Yang, M. Ye, Minghan Ye, J. H. Yin, Z. Y. You, Boxiang Yu, C. X. Yu, J. S. Yu, Chang-Zheng Yuan, Y. Yuan, A. Yuncu, A. A. Zafar, Y. Zeng, Z. Zeng, B. X. Zhang, B. Y. Zhang, C. C. Zhang, D. H. Zhang, H. H. Zhang, Hongyu Zhang, J. Zhang, J. L. Zhang, J. Q. Zhang, J. W. Zhang, Jianyong Zhang, J. Z. Zhang, K. Zhang, L. Zhang, S. Q. Zhang, X. Y. Zhang, Y. Zhang, Y. Zhang, Y. H. Zhang, Y. T. Zhang, Yu Zhang, Z. H. Zhang, Z. P. Zhang, Z. Y. Zhang, G. Zhao, J. W. Zhao, J. Y. Zhao, J. Z. Zhao, Lei Zhao, Ling Zhao, Ming-Gang Zhao, Q. Zhao, Shujun Zhao, T. C. Zhao, Yubin Zhao, Zhengguo Zhao, Alexey Zhemchugov, B. Zheng, Jianping Zheng, W. J. Zheng, Y. H. Zheng, B. Zhong, L. Zhou, X. Zhou, X. K. Zhou, X. R. Zhou, X. Y. Zhou, Y. X. Zhou, K. Zhu, Kejun Zhu, S. Zhu, S. H. Zhu, X. L. Zhu, Y. C. Zhu, Y. S. Zhu, Zian Zhu, J. Zhuang, L. Zotti, B. S. Zou, Jiaheng Zou

• The decay 𝐽/𝜓→𝛾⁢𝛾⁢𝜙 is studied using a sample of 1.31×109  𝐽/𝜓 events collected with the BESIII detector. Two structures around 1475  MeV/𝑐2 and 1835  MeV/𝑐2 are observed in the 𝛾⁢𝜙 invariant mass spectrum for the first time. With a fit on the 𝛾⁢𝜙 invariant mass, which takes into account the interference between the two structures, and a simple analysis of the angular distribution, the structure around 1475  MeV/𝑐2 is found to favor an assignment as the 𝜂⁡(1475) and the mass and width for the structure around 1835  MeV/𝑐2 are consistent with the 𝑋⁡(1835). The statistical significances of the two structures are 13.5⁢𝜎 and 6.3⁢𝜎, respectively. The results indicate that both 𝜂⁡(1475) and 𝑋⁡(1835) contain a sizeable 𝑠⁢¯𝑠 component.