A possible explanation of the threshold enhancement in the process e^+e^-→∧■  

作　　者：Li-Ye Xiao Xin-Zhen Weng Xian-Hui Zhong Shi-Lin Zhu 肖立叶;翁新震;钟显辉;朱世琳(School of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,Beijing 100871,China;Center of High Energy Physics,Peking University,Beijing 100871,China;Department of Physics,Hunan Normal University,and Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education,Changsha 410081,China;Synergetic Innovation Center for Quantum Effects and Applications(SICQEA),Hunan Normal University,Changsha 410081,China;Collaborative Innovation Center of Quantum Matter,Beijing 100871,China)

机构地区：[1]School of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,Beijing 100871,China [2]Center of High Energy Physics,Peking University,Beijing 100871,China [3]Department of Physics,Hunan Normal University,and Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education,Changsha 410081,China [4]Synergetic Innovation Center for Quantum Effects and Applications(SICQEA),Hunan Normal University,Changsha 410081,China [5]Collaborative Innovation Center of Quantum Matter,Beijing 100871,China

出　　处：《Chinese Physics C》2019年第11期49-57,共9页中国物理C（英文版）

基　　金：Supported by the National Natural Science Foundation of China(11575008,11621131001,11775078,U1832173);National Key Basic Research Program of China(2015CB856700);In part supported by China Postdoctoral Science Foundation(2017M620492)

摘　　要：Inspired by the recent measurement of the process e+e-→∧■,we calculate the mass spectrum of the 0 meson with the GI model.For the excited vector strangeonium states ?（3 S,4 S,5 S,6 S） and ?（2 D,3 D,4 D,5 D）,we investigate the electronic decay width with the Van Royen-Weisskopf formula,and the partial widths of the ∧■,■,and■ decay modes with the extended quark-pair creation model.We find that the electronic decay width of the D-wave vector strangeonium is about 3～8 times larger than of the S-wave vector strangeonium.Around 2232 Me V,the partial decay width of the ∧■ mode can be up to several MeV for ?（33 S1）,while the partial ∧■ decay width of ?（23 D1） is O(10-3) keV.If the threshold enhancement reported by the BESIII collaboration arises from the strangeonium meson,this state is very likely the ?（33 S1） state.We also note that the ∧■ and∑+■partial decay widths of the states ?（33 D1） and ?（43 S1） are several MeV,which is sufficient to be observed in future experiments.Inspired by the recent measurement of the process e^+e^-→ΛΛ^-,we calculate the mass spectrum of the Φ meson with the GI model.For the excited vector strangeonium states Φ(3S,4S,5S,6S)and Φ(2D,3D,4D,5D),we investigate the electronic decay width with the Van Royen-Weisskopf formula,and the partial widths of theΛΛ^-,■^-(*)■^-+,and Σ+(*)Σ^- -(*)decay modes with the extended quark-pair creation model.We find that the electronic decay width of the D-wave vector strangeonium is about 3~8 times larger than of the S-wave vector strangeonium.Around 2232 MeV,the partial decay width of theΛΛ^-mode can be up to several MeV for Φ(33S1),while the partialΛΛ^-decay width of Φ(23D1)is O(10^-3)keV.If the threshold enhancement reported by the BESIII collaboration arises from the strangeonium meson,this state is very likely the?(33S1)state.We also note that theΛΛ^- and Σ+Σ^--partial decay widths of the states Φ(33D1)and Φ(43S1)are several MeV,which is sufficient to be observed in future experiments.

关 键 词：SPECTRUM GI MODE ΛΛ^-decay 

分 类 号：O57[理学—粒子物理与原子核物理]