51. Two-photon widths of the $χ_{c0, 2}$ states and helicity analysis for $χ_{c2}\arγγ$}
- Author
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BESIII Collaboration, M. Ablikim(Institute of High Energy Physics, Beijing, P. R. China), M. N. Achasov(G.I. Budker Institute of Nuclear Physics SB RAS), D. J. Ambrose(University of Rochester, Rochester, New York, USA), F. F. An(Institute of High Energy Physics, Beijing, P. R. China), Q. An(University of Science and Technology of China, Hefei, P. R. China), Z. H. An(Institute of High Energy Physics, Beijing, P. R. China), J. Z. Bai(Institute of High Energy Physics, Beijing, P. R. China), R. B. Ferroli(INFN Laboratori Nazionali di Frascati, Frascati, Italy), Y. Ban(Peking University, Beijing, P. R. China), J. Becker(Bochum Ruhr-University, Bochum, Germany), N. Berger(Institute of High Energy Physics, Beijing, P. R. China), M. B. Bertani(INFN Laboratori Nazionali di Frascati, Frascati, Italy), J. M. Bian(University of Minnesota, Minneapolis, MN, USA), E. Boger(20, a), O. Bondarenko(KVI/University of Groningen, Groningen, The Netherlands), I. Boyko(Joint Institute for Nuclear Research, Dubna, Russia), R. A. Briere(Carnegie Mellon University, Pittsburgh, PA, USA), V. Bytev(Joint Institute for Nuclear Research, Dubna, Russia), X. Cai(Institute of High Energy Physics, Beijing, P. R. China), A. C. Calcaterra(INFN Laboratori Nazionali di Frascati, Frascati, Italy), G. F. Cao(Institute of High Energy Physics, Beijing, P. R. China), J. F. Chang(Institute of High Energy Physics, Beijing, P. R. China), G. Chelkov(20, a), G. Chen(Institute of High Energy Physics, Beijing, P. R. China), H. S. Chen(Institute of High Energy Physics, Beijing, P. R. China), J. C. Chen(Institute of High Energy Physics, Beijing, P. R. China), M. L. Chen(Institute of High Energy Physics, Beijing, P. R. China), S. J. Chen(Nanjing University, Nanjing, P. R. China), Y. Chen(Institute of High Energy Physics, Beijing, P. R. China), Y. B. Chen(Institute of High Energy Physics, Beijing, P. R. China), H. P. Cheng(Huangshan College, Huangshan, P. R. China), Y. P. Chu(Institute of High Energy Physics, Beijing, P. R. China), D. Cronin-Hennessy(University of Minnesota, Minneapolis, MN, USA), H. L. Dai(Institute of High Energy Physics, Beijing, P. R. China), J. P. Dai(Institute of High Energy Physics, Beijing, P. R. China), D. Dedovich(Joint Institute for Nuclear Research, Dubna, Russia), Z. Y. Deng(Institute of High Energy Physics, Beijing, P. R. China), A. Denig(Johannes Gutenberg University of Mainz, Mainz, Germany), I. Denysenko(20, b), M. Destefanis(University of Turin and INFN, Turin, Italy), W. M. Ding(Shandong University, Jinan, P. R. China), Y. Ding(Liaoning University, Shenyang, P. R. China), L. Y. Dong(Institute of High Energy Physics, Beijing, P. R. China), M. Y. Dong(Institute of High Energy Physics, Beijing, P. R. China), S. X. Du(Zhengzhou University, Zhengzhou, P. R. China), J. Fang(Institute of High Energy Physics, Beijing, P. R. China), S. S. Fang(Institute of High Energy Physics, Beijing, P. R. China), L. Fava(44, c), F. Feldbauer(Bochum Ruhr-University, Bochum, Germany), C. Q. Feng(University of Science and Technology of China, Hefei, P. R. China), C. D. Fu(Institute of High Energy Physics, Beijing, P. R. China), J. L. Fu(Nanjing University, Nanjing, P. R. China), Y. Gao(Tsinghua University, Beijing, P. R. China), C. Geng(University of Science and Technology of China, Hefei, P. R. China), K. Goetzen(GSI Helmholtzcentre for Heavy Ion Research GmbH, Darmstadt, Germany), W. X. Gong(Institute of High Energy Physics, Beijing, P. R. China), W. Gradl(Johannes Gutenberg University of Mainz, Mainz, Germany), M. Greco(University of Turin and INFN, Turin, Italy), M. H. Gu(Institute of High Energy Physics, Beijing, P. R. China), Y. T. Gu(GuangXi University, Nanning, P.R.China), Y. H. Guan(Graduate University of Chinese Academy of Sciences, Beijing, P. R. China), A. Q. Guo(Nankai University, Tianjin, P. R. China), L. B. Guo(Nanjing Normal University, Nanjing, P. R. China), Y. P. Guo(Nankai University, Tianjin, P. R. China), Y. L. Han(Institute of High Energy Physics, Beijing, P. R. China), X. Q. Hao(Institute of High Energy Physics, Beijing, P. R. China), F. A. Harris(University of Hawaii, Honolulu, Hawaii, USA), K. L. He(Institute of High Energy Physics, Beijing, P. R. China), M. He(Institute of High Energy Physics, Beijing, P. R. China), Z. Y. He(Nankai University, Tianjin, P. R. China), T. Held(Bochum Ruhr-University, Bochum, Germany), Y. K. Heng(Institute of High Energy Physics, Beijing, P. R. China), Z. L. Hou(Institute of High Energy Physics, Beijing, P. R. China), H. M. Hu(Institute of High Energy Physics, Beijing, P. R. China), J. F. Hu(Graduate University of Chinese Academy of Sciences, Beijing, P. R. China), T. Hu(Institute of High Energy Physics, Beijing, P. R. China), B. Huang(Institute of High Energy Physics, Beijing, P. R. China), G. M. Huang(Huazhong Normal University, Wuhan, P. R. China), J. S. Huang(Henan Normal University, Xinxiang, P. R. China), X. T. Huang(Shandong University, Jinan, P. R. China), Y. P. Huang(Institute of High Energy Physics, Beijing, P. R. China), T. Hussain(University of the Punjab, Lahore, Pakistan), C. S. Ji(University of Science and Technology of China, Hefei, P. R. China), Q. Ji(Institute of High Energy Physics, Beijing, P. R. China), X. B. Ji(Institute of High Energy Physics, Beijing, P. R. China), X. L. Ji(Institute of High Energy Physics, Beijing, P. R. China), L. K. Jia(Institute of High Energy Physics, Beijing, P. R. China), L. L. Jiang(Institute of High Energy Physics, Beijing, P. R. China), X. S. Jiang(Institute of High Energy Physics, Beijing, P. R. China), J. B. Jiao(Shandong University, Jinan, P. R. China), Z. Jiao(Huangshan College, Huangshan, P. R. China), D. P. Jin(Institute of High Energy Physics, Beijing, P. R. China), S. Jin(Institute of High Energy Physics, Beijing, P. R. China), F. F. Jing(Tsinghua University, Beijing, P. R. China), N. Kalantar-Nayestanaki(KVI/University of Groningen, Groningen, The Netherlands), M. Kavatsyuk(KVI/University of Groningen, Groningen, The Netherlands), W. Kuehn(Universitaet Giessen, Giessen, Germany), W. Lai(Institute of High Energy Physics, Beijing, P. R. China), J. S. Lange(Universitaet Giessen, Giessen, Germany), J. K. C. Leung(The University of Hong Kong, Pokfulam, Hong Kong), C. H. Li(Institute of High Energy Physics, Beijing, P. R. China), Cheng Li(University of Science and Technology of China, Hefei, P. R. China), Cui Li(University of Science and Technology of China, Hefei, P. R. China), D. M. Li(Zhengzhou University, Zhengzhou, P. R. China), F. Li(Institute of High Energy Physics, Beijing, P. R. China), G. Li(Institute of High Energy Physics, Beijing, P. R. China), H. B. Li(Institute of High Energy Physics, Beijing, P. R. China), J. C. Li(Institute of High Energy Physics, Beijing, P. R. China), K. Li(Hangzhou Normal University, Hangzhou, P. R. China), Lei Li(Institute of High Energy Physics, Beijing, P. R. China), N. B. Li(Nanjing Normal University, Nanjing, P. R. China), Q. J. Li(Institute of High Energy Physics, Beijing, P. R. China), S. L. Li(Institute of High Energy Physics, Beijing, P. R. China), W. D. Li(Institute of High Energy Physics, Beijing, P. R. China), W. G. Li(Institute of High Energy Physics, Beijing, P. R. China), X. L. Li(Shandong University, Jinan, P. R. China), X. N. Li(Institute of High Energy Physics, Beijing, P. R. China), X. Q. Li(Nankai University, Tianjin, P. R. China), X. R. Li(Seoul National University, Seoul, Korea), Z. B. Li(Sun Yat-Sen University, Guangzhou, P. R. China), H. Liang(University of Science and Technology of China, Hefei, P. R. China), Y. F. Liang(Sichuan University, Chengdu, P. R. China), Y. T. Liang(Universitaet Giessen, Giessen, Germany), G. R. Liao(Tsinghua University, Beijing, P. R. China), X. T. Liao(Institute of High Energy Physics, Beijing, P. R. China), B. J. Liu(Institute of High Energy Physics, Beijing, P. R. China), C. L. Liu(Carnegie Mellon University, Pittsburgh, PA, USA), C. X. Liu(Institute of High Energy Physics, Beijing, P. R. China), C. Y. Liu(Institute of High Energy Physics, Beijing, P. R. China), F. H. Liu(Shanxi University, Taiyuan, P. R. China), Fang Liu(Institute of High Energy Physics, Beijing, P. R. China), Feng Liu(Huazhong Normal University, Wuhan, P. R. China), H. Liu(Shanxi University, Taiyuan, P. R. China), H. B. Liu(Graduate University of Chinese Academy of Sciences, Beijing, P. R. China), H. H. Liu(Henan University of Science and Technology, Luoyang, P. R. China), H. M. Liu(Institute of High Energy Physics, Beijing, P. R. China), H. W. Liu(Institute of High Energy Physics, Beijing, P. R. China), J. P. Liu(Wuhan University, Wuhan, P. R. China), Kun Liu(Peking University, Beijing, P. R. China), Kai Liu(Graduate University of Chinese Academy of Sciences, Beijing, P. R. China), K. Y. Liu(Liaoning University, Shenyang, P. R. China), P. L. Liu(Shandong University, Jinan, P. R. China), S. B. Liu(University of Science and Technology of China, Hefei, P. R. China), X. Liu(Institute of High Energy Physics, Beijing, P. R. China), X. H. Liu(Institute of High Energy Physics, Beijing, P. R. China), Y. B. Liu(Nankai University, Tianjin, P. R. China), Y. Liu(Institute of High Energy Physics, Beijing, P. R. China), Z. A. Liu(Institute of High Energy Physics, Beijing, P. R. China), Zhiqiang Liu(Institute of High Energy Physics, Beijing, P. R. China), Zhiqing Liu(Institute of High Energy Physics, Beijing, P. R. China), H. Loehner(KVI/University of Groningen, Groningen, The Netherlands), G. R. Lu(Henan Normal University, Xinxiang, P. R. China), H. J. Lu(Huangshan College, Huangshan, P. R. China), J. G. Lu(Institute of High Energy Physics, Beijing, P. R. China), Q. W. Lu(Shanxi University, Taiyuan, P. R. China), X. R. Lu(Graduate University of Chinese Academy of Sciences, Beijing, P. R. China), Y. P. Lu(Institute of High Energy Physics, Beijing, P. R. China), C. L. Luo(Nanjing Normal University, Nanjing, P. R. China), M. X. Luo(Zhejiang University, Hangzhou, P. R. China), T. Luo(University of Hawaii, Honolulu, Hawaii, USA), X. L. Luo(Institute of High Energy Physics, Beijing, P. R. China), M. Lv(Institute of High Energy Physics, Beijing, P. R. China), C. L. Ma(Graduate University of Chinese Academy of Sciences, Beijing, P. R. China), F. C. Ma(Liaoning University, Shenyang, P. R. China), H. L. Ma(Institute of High Energy Physics, Beijing, P. R. China), Q. M. Ma(Institute of High Energy Physics, Beijing, P. R. China), S. Ma(Institute of High Energy Physics, Beijing, P. R. China), T. Ma(Institute of High Energy Physics, Beijing, P. R. China), X. Y. Ma(Institute of High Energy Physics, Beijing, P. R. China), Y. Ma(Institute of High Energy Physics, Beijing, P. R. China), F. E. Maas(Helmholtz Institute Mainz, Mainz, Germany), M. Maggiora(University of Turin and INFN, Turin, Italy), Q. A. Malik(University of the Punjab, Lahore, Pakistan), H. Mao(Institute of High Energy Physics, Beijing, P. R. China), Y. J. Mao(Peking University, Beijing, P. R. China), Z. P. Mao(Institute of High Energy Physics, Beijing, P. R. China), J. G. Messchendorp(KVI/University of Groningen, Groningen, The Netherlands), J. Min(Institute of High Energy Physics, Beijing, P. R. China), T. J. Min(Institute of High Energy Physics, Beijing, P. R. China), R. E. Mitchell(Indiana University, Bloomington, Indiana, USA), X. H. Mo(Institute of High Energy Physics, Beijing, P. R. China), C. Morales Morales(Helmholtz Institute Mainz, Mainz, Germany), C. Motzko(Bochum Ruhr-University, Bochum, Germany), N. Yu. Muchnoi(G.I. Budker Institute of Nuclear Physics SB RAS), Y. Nefedov(Joint Institute for Nuclear Research, Dubna, Russia), C. Nicholson(Graduate University of Chinese Academy of Sciences, Beijing, P. R. China), I. B. Nikolaev(G.I. Budker Institute of Nuclear Physics SB RAS), Z. Ning(Institute of High Energy Physics, Beijing, P. R. China), S. L. Olsen(Seoul National University, Seoul, Korea), Q. Ouyang(Institute of High Energy Physics, Beijing, P. R. China), S. P. Pacetti(18, d), J. W. Park(Seoul National University, Seoul, Korea), M. Pelizaeus(University of Hawaii, Honolulu, Hawaii, USA), K. Peters(GSI Helmholtzcentre for Heavy Ion Research GmbH, Darmstadt, Germany), J. L. Ping(Nanjing Normal University, Nanjing, P. R. China), R. G. Ping(Institute of High Energy Physics, Beijing, P. R. China), R. Poling(University of Minnesota, Minneapolis, MN, USA), E. Prencipe(Johannes Gutenberg University of Mainz, Mainz, Germany), C. S. J. Pun(The University of Hong Kong, Pokfulam, Hong Kong), M. Qi(Nanjing University, Nanjing, P. R. China), S. Qian(Institute of High Energy Physics, Beijing, P. R. China), C. F. Qiao(Graduate University of Chinese Academy of Sciences, Beijing, P. R. China), X. S. Qin(Institute of High Energy Physics, Beijing, P. R. China), Y. Qin(Peking University, Beijing, P. R. China), Z. H. Qin(Institute of High Energy Physics, Beijing, P. R. China), J. F. Qiu(Institute of High Energy Physics, Beijing, P. R. China), K. H. Rashid(University of the Punjab, Lahore, Pakistan), G. Rong(Institute of High Energy Physics, Beijing, P. R. China), X. D. Ruan(GuangXi University, Nanning, P.R.China), A. Sarantsev(20, e), J. Schulze(Bochum Ruhr-University, Bochum, Germany), M. Shao(University of Science and Technology of China, Hefei, P. R. China), C. P. Shen(38, f), X. Y. Shen(Institute of High Energy Physics, Beijing, P. R. China), H. Y. Sheng(Institute of High Energy Physics, Beijing, P. R. China), M. R. Shepherd(Indiana University, Bloomington, Indiana, USA), X. Y. Song(Institute of High Energy Physics, Beijing, P. R. China), S. Spataro(University of Turin and INFN, Turin, Italy), B. Spruck(Universitaet Giessen, Giessen, Germany), D. H. Sun(Institute of High Energy Physics, Beijing, P. R. China), G. X. Sun(Institute of High Energy Physics, Beijing, P. R. China), J. F. Sun(Henan Normal University, Xinxiang, P. R. China), S. S. Sun(Institute of High Energy Physics, Beijing, P. R. China), X. D. Sun(Institute of High Energy Physics, Beijing, P. R. China), Y. J. Sun(University of Science and Technology of China, Hefei, P. R. China), Y. Z. Sun(Institute of High Energy Physics, Beijing, P. R. China), Z. J. Sun(Institute of High Energy Physics, Beijing, P. R. China), Z. T. Sun(University of Science and Technology of China, Hefei, P. R. China), C. J. Tang(Sichuan University, Chengdu, P. R. China), X. Tang(Institute of High Energy Physics, Beijing, P. R. China), E. H. Thorndike(University of Rochester, Rochester, New York, USA), H. L. Tian(Institute of High Energy Physics, Beijing, P. R. China), D. Toth(University of Minnesota, Minneapolis, MN, USA), M. U. Ulrich(Universitaet Giessen, Giessen, Germany), G. S. Varner(University of Hawaii, Honolulu, Hawaii, USA), B. Wang(GuangXi University, Nanning, P.R.China), B. Q. Wang(Peking University, Beijing, P. R. China), K. Wang(Institute of High Energy Physics, Beijing, P. R. China), L. L. Wang(China Center of Advanced Science and Technology, Beijing, P. R. China), L. S. Wang(Institute of High Energy Physics, Beijing, P. R. China), M. Wang(Shandong University, Jinan, P. R. China), P. Wang(Institute of High Energy Physics, Beijing, P. R. China), P. L. Wang(Institute of High Energy Physics, Beijing, P. R. China), Q. Wang(Peking University, Beijing, P. R. China), Q. J. Wang(Institute of High Energy Physics, Beijing, P. R. China), S. G. Wang(Peking University, Beijing, P. R. China), X. F. Wang(Henan Normal University, Xinxiang, P. R. China), X. L. Wang(University of Science and Technology of China, Hefei, P. R. China), Y. D. Wang(University of Science and Technology of China, Hefei, P. R. China), Y. F. Wang(Institute of High Energy Physics, Beijing, P. R. China), Y. Q. Wang(Shandong University, Jinan, P. R. China), Z. Wang(Institute of High Energy Physics, Beijing, P. R. China), Z. G. Wang(Institute of High Energy Physics, Beijing, P. R. China), Z. Y. Wang(Institute of High Energy Physics, Beijing, P. R. China), D. H. Wei(Guangxi Normal University, Guilin, P. R. China), P. Weidenkaff(Johannes Gutenberg University of Mainz, Mainz, Germany), Q. G. Wen(University of Science and Technology of China, Hefei, P. R. China), S. P. Wen(Institute of High Energy Physics, Beijing, P. R. China), M. W. Werner(Universitaet Giessen, Giessen, Germany), U. Wiedner(Bochum Ruhr-University, Bochum, Germany), L. H. Wu(Institute of High Energy Physics, Beijing, P. R. China), N. Wu(Institute of High Energy Physics, Beijing, P. R. China), S. X. Wu(University of Science and Technology of China, Hefei, P. R. China), W. Wu(Nankai University, Tianjin, P. R. China), Z. Wu(Institute of High Energy Physics, Beijing, P. R. China), L. G. Xia(Tsinghua University, Beijing, P. R. China), Z. J. Xiao(Nanjing Normal University, Nanjing, P. R. China), Y. G. Xie(Institute of High Energy Physics, Beijing, P. R. China), Q. L. Xiu(Institute of High Energy Physics, Beijing, P. R. China), G. F. Xu(Institute of High Energy Physics, Beijing, P. R. China), G. M. Xu(Peking University, Beijing, P. R. China), H. Xu(Institute of High Energy Physics, Beijing, P. R. China), Q. J. Xu(Hangzhou Normal University, Hangzhou, P. R. China), X. P. Xu(Soochow University, Suzhou, China), Y. Xu(Nankai University, Tianjin, P. R. China), Z. R. Xu(University of Science and Technology of China, Hefei, P. R. China), F. Xue(Huazhong Normal University, Wuhan, P. R. China), Z. Xue(Institute of High Energy Physics, Beijing, P. R. China), L. Yan(University of Science and Technology of China, Hefei, P. R. China), W. B. Yan(University of Science and Technology of China, Hefei, P. R. China), Y. H. Yan(Hunan University, Changsha, P. R. China), H. X. Yang(Institute of High Energy Physics, Beijing, P. R. China), T. Yang(GuangXi University, Nanning, P.R.China), Y. Yang(Huazhong Normal University, Wuhan, P. R. China), Y. X. Yang(Guangxi Normal University, Guilin, P. R. China), H. Ye(Institute of High Energy Physics, Beijing, P. R. China), M. Ye(Institute of High Energy Physics, Beijing, P. R. China), M. H. Ye(China Center of Advanced Science and Technology, Beijing, P. R. China), B. X. Yu(Institute of High Energy Physics, Beijing, P. R. China), C. X. Yu(Nankai University, Tianjin, P. R. China), J. S. Yu(Lanzhou University, Lanzhou, P. R. China), S. P. Yu(Shandong University, Jinan, P. R. China), C. Z. Yuan(Institute of High Energy Physics, Beijing, P. R. China), W. L. Yuan(Nanjing Normal University, Nanjing, P. R. China), Y. Yuan(Institute of High Energy Physics, Beijing, P. R. China), A. A. Zafar(University of the Punjab, Lahore, Pakistan), A. Z. Zallo(INFN Laboratori Nazionali di Frascati, Frascati, Italy), Y. Zeng(Hunan University, Changsha, P. R. China), B. X. Zhang(Institute of High Energy Physics, Beijing, P. R. China), B. Y. Zhang(Institute of High Energy Physics, Beijing, P. R. China), C. C. Zhang(Institute of High Energy Physics, Beijing, P. R. China), D. H. Zhang(Institute of High Energy Physics, Beijing, P. R. China), H. H. Zhang(Sun Yat-Sen University, Guangzhou, P. R. China), H. Y. Zhang(Institute of High Energy Physics, Beijing, P. R. China), J. Zhang(Nanjing Normal University, Nanjing, P. R. China), J. G. Zhang(Henan Normal University, Xinxiang, P. R. China), J. Q. Zhang(Institute of High Energy Physics, Beijing, P. R. China), J. W. Zhang(Institute of High Energy Physics, Beijing, P. R. China), J. Y. Zhang(Institute of High Energy Physics, Beijing, P. R. China), J. Z. Zhang(Institute of High Energy Physics, Beijing, P. R. China), L. Zhang(Nanjing University, Nanjing, P. R. China), S. H. Zhang(Institute of High Energy Physics, Beijing, P. R. China), T. R. Zhang(Nanjing Normal University, Nanjing, P. R. China), X. J. Zhang(Institute of High Energy Physics, Beijing, P. R. China), X. Y. Zhang(Shandong University, Jinan, P. R. China), Y. Zhang(Institute of High Energy Physics, Beijing, P. R. China), Y. H. Zhang(Institute of High Energy Physics, Beijing, P. R. China), Y. S. Zhang(GuangXi University, Nanning, P.R.China), Z. P. Zhang(University of Science and Technology of China, Hefei, P. R. China), Z. Y. Zhang(Wuhan University, Wuhan, P. R. China), G. Zhao(Institute of High Energy Physics, Beijing, P. R. China), H. S. Zhao(Institute of High Energy Physics, Beijing, P. R. China), J. W. Zhao(Institute of High Energy Physics, Beijing, P. R. China), K. X. Zhao(Nanjing Normal University, Nanjing, P. R. China), Lei Zhao(University of Science and Technology of China, Hefei, P. R. China), Ling Zhao(Institute of High Energy Physics, Beijing, P. R. China), M. G. Zhao(Nankai University, Tianjin, P. R. China), Q. Zhao(Institute of High Energy Physics, Beijing, P. R. China), S. J. Zhao(Zhengzhou University, Zhengzhou, P. R. China), T. C. Zhao(Institute of High Energy Physics, Beijing, P. R. China), X. H. Zhao(Nanjing University, Nanjing, P. R. China), Y. B. Zhao(Institute of High Energy Physics, Beijing, P. R. China), Z. G. Zhao(University of Science and Technology of China, Hefei, P. R. China), A. Zhemchugov(20, a), B. Zheng(University of South China, Hengyang, P. R. China), J. P. Zheng(Institute of High Energy Physics, Beijing, P. R. China), Y. H. Zheng(Graduate University of Chinese Academy of Sciences, Beijing, P. R. China), Z. P. Zheng(Institute of High Energy Physics, Beijing, P. R. China), B. Zhong(Institute of High Energy Physics, Beijing, P. R. China), J. Zhong(Bochum Ruhr-University, Bochum, Germany), L. Zhou(Institute of High Energy Physics, Beijing, P. R. China), X. K. Zhou(Graduate University of Chinese Academy of Sciences, Beijing, P. R. China), X. R. Zhou(University of Science and Technology of China, Hefei, P. R. China), C. Zhu(Institute of High Energy Physics, Beijing, P. R. China), K. Zhu(Institute of High Energy Physics, Beijing, P. R. China), K. J. Zhu(Institute of High Energy Physics, Beijing, P. R. China), S. H. Zhu(Institute of High Energy Physics, Beijing, P. R. China), X. L. Zhu(Tsinghua University, Beijing, P. R. China), X. W. Zhu(Institute of High Energy Physics, Beijing, P. R. China), Y. M. Zhu(Nankai University, Tianjin, P. R. China), Y. S. Zhu(Institute of High Energy Physics, Beijing, P. R. China), Z. A. Zhu(Institute of High Energy Physics, Beijing, P. R. China), J. Zhuang(Institute of High Energy Physics, Beijing, P. R. China), B. S. Zou(Institute of High Energy Physics, Beijing, P. R. China), J. H. Zou(Institute of High Energy Physics, Beijing, P. R. China), and J. X. Zuo(Institute of High Energy Physics, Beijing, P. R. China)
- Subjects
hep-ex ,Astrophysics::High Energy Astrophysical Phenomena ,High Energy Physics::Experiment ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
Based on a data sample of 106 M $\psi^{\prime}$ events collected with the BESIII detector, the decays $\psi^{\prime}\ar\gamma\chi_{c0, 2}$,$\chi_{c0, 2}\ar\gamma\gamma$ are studied to determine the two-photon widths of the $\chi_{c0, 2}$ states. The two-photon decay branching fractions are determined to be ${\cal B}(\chi_{c0}\ar\gamma\gamma) = (2.24\pm 0.19\pm 0.12\pm 0.08)\times 10^{-4}$ and ${\cal B}(\chi_{c2}\ar\gamma\gamma) = (3.21\pm 0.18\pm 0.17\pm 0.13)\times 10^{-4}$. From these, the two-photon widths are determined to be $\Gamma_{\gamma \gamma}(\chi_{c0}) = (2.33\pm0.20\pm0.13\pm0.17)$ keV, $\Gamma_{\gamma \gamma}(\chi_{c2}) = (0.63\pm0.04\pm0.04\pm0.04)$ keV, and $\cal R$ $=\Gamma_{\gamma \gamma}(\chi_{c2})/\Gamma_{\gamma \gamma}(\chi_{c0})=0.271\pm 0.029\pm 0.013\pm 0.027$, where the uncertainties are statistical, systematic, and those from the PDG ${\cal B}(\psi^{\prime}\ar\gamma\chi_{c0,2})$ and $\Gamma(\chi_{c0,2})$ errors, respectively. The ratio of the two-photon widths for helicity $\lambda=0$ and helicity $\lambda=2$ components in the decay $\chi_{c2}\ar\gamma\gamma$ is measured for the first time to be $f_{0/2} =\Gamma^{\lambda=0}_{\gamma\gamma}(\chi_{c2})/\Gamma^{\lambda=2}_{\gamma\gamma}(\chi_{c2}) = 0.00\pm0.02\pm0.02$.
- Published
- 2015