Observation of a near - threshold enhancement in the pp mass spectrum from radiative J / ψ → γpp decays ( BES Collaboration )
نویسندگان
چکیده
(BES Collaboration) J. Z. Bai, Y. Ban, J. G. Bian, X. Cai, J. F. Chang, H. F. Chen, H. S. Chen, J. Chen, Jie Chen, J. C. Chen, Y. B. Chen, S. P. Chi, Y. P. Chu, X. Z. Cui, Y. M. Dai, Y. S. Dai, L. Y. Dong, S. X. Du, Z. Z. Du, W. Dunwoodie, J. Fang, S. S. Fang, C. D. Fu, H. Y. Fu, L. P. Fu, C. S. Gao, M. L. Gao, Y. N. Gao, M. Y. Gong, W. X. Gong, S. D. Gu, Y. N. Guo, Y. Q. Guo, Z. J. Guo, S. W. Han, F. A. Harris, J. He, K. L. He, M. He, X. He, Y. K. Heng, T. Hong, H. M. Hu, T. Hu, G. S. Huang, L. Huang, X. P. Huang, J. M. Izen, X. B. Ji, C. H. Jiang, X. S. Jiang, D. P. Jin, S. Jin, Y. Jin, B. D. Jones, Z. J. Ke, D. Kong, Y. F. Lai, F. Li, G. Li, H. H. Li, J. Li, J. C. Li, K. Li, Q. J. Li, R. B. Li, R. Y. Li, W. Li, W. G. Li, X. Q. Li, X. S. Li, C. F. Liu, C. X. Liu, Fang Liu, F. Liu, H. M. Liu, J. B. Liu, J. P. Liu, R. G. Liu, Y. Liu, Z. A. Liu, Z. X. Liu, X. C. Lou, G. R. Lu, F. Lu, H. J. Lu, J. G. Lu, Z. J. Lu, X. L. Luo, E. C. Ma, F. C. Ma, J. M. Ma, R. Malchow, Z. P. Mao, X. C. Meng, X. H. Mo, J. Nie, Z. D. Nie, S. L. Olsen, D. Paluselli, H. P. Peng, N. D. Qi, C. D. Qian, J. F. Qiu, G. Rong, D. L. Shen, H. Shen, X. Y. Shen, H. Y. Sheng, F. Shi, L. W. Song, H. S. Sun, S. S. Sun, Y. Z. Sun, Z. J. Sun, S. Q. Tang, X. Tang, D. Tian, Y. R. Tian, W. Toki, G. L. Tong, G. S. Varner, J. Wang, J. Z. Wang, L. Wang, L. S. Wang, M. Wang, Meng Wang, P. Wang, P. L. Wang, W. F. Wang, Y. F. Wang, Zhe Wang, Z. Wang, Zheng Wang, Z. Y. Wang, C. L. Wei, N. Wu, X. M. Xia, X. X. Xie, G. F. Xu, Y. Xu, S. T. Xue, M. L. Yan, W. B. Yan, G. A. Yang, H. X. Yang, J. Yang, S. D. Yang, M. H. Ye, Y. X. Ye, J. Ying, C. S. Yu, G. W. Yu, C. Z. Yuan, J. M. Yuan, Y. Yuan, Q. Yue, S. L. Zang, Y. Zeng, B. X. Zhang, B. Y. Zhang, C. C. Zhang, D. H. Zhang, H. Y. Zhang, J. Zhang, J. M. Zhang, J. W. Zhang, L. S. Zhang, Q. J. Zhang, S. Q. Zhang, X. Y. Zhang, Y. J. Zhang, Yiyun Zhang, Y. Y. Zhang, Z. P. Zhang, D. X. Zhao, Jiawei Zhao, J. W. Zhao, P. P. Zhao, W. R. Zhao, Y. B. Zhao, Z. G. Zhao, J. P. Zheng, L. S. Zheng, Z. P. Zheng, X. C. Zhong, B. Q. Zhou, G. M. Zhou, L. Zhou, N. F. Zhou, K. J. Zhu, Q. M. Zhu, Yingchun Zhu, Y. C. Zhu, Y. S. Zhu, Z. A. Zhu, B. A. Zhuang, B. S. Zou. 1 Institute of High Energy Physics, Beijing 100039, People’s Republic of China 2 China Center of Advanced Science and Technology, Beijing 100080, People’s Republic of China 3 Colorado State University, Fort Collins, Colorado 80523 4 Henan Normal University, Xinxiang 453002, People’s Republic of China 5 Huazhong Normal University, Wuhan 430079, People’s Republic of China 6 Hunan University, Changsha 410082, People’s Republic of China 7 Liaoning University, Shenyang 110036, People’s Republic of China 8 Nankai University, Tianjin 300071, People’s Republic of China 9 Peking University, Beijing 100871, People’s Republic of China 10 Shandong University, Jinan 250100, People’s Republic of China 11 Shanghai Jiaotong University, Shanghai 200030, People’s Republic of China 12 Sichuan University, Chengdu 610064, People’s Republic of China 13 Stanford Linear Accelerator Center, Stanford, California 94309 14 Tsinghua University, Beijing 100084, People’s Republic of China 15 University of Hawaii, Honolulu, Hawaii 96822 16 University of Science and Technology of China, Hefei 230026, People’s Republic of China 17 University of Texas at Dallas, Richardson, Texas 75083-0688 18 Wuhan University, Wuhan 430072, People’s Republic of China 19 Zhejiang University, Hangzhou 310028, People’s Republic of China ∗ Visiting professor at the University of Michigan, Ann Arbor, MI 48109 (March 7, 2003)
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