Λc重子谱疑难(英文)  

Puzzle of the Λ_c Spectrum

作　　者：吕齐放 董宇兵[2,3] 刘翔 MATSUKI Takayuki[6,7] LV Qifang;DONG Yubing;LIU Xiang;MATSUKI Takayuki(Department of Physics, Hunan Normal University, Changsha 410081, China;Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China;Theoretical Physics Center for Science Facilities （TPCSF）, Chinese Academy of Sciences, Beijing 100049, China;School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China;Research Center for Hadron and CSR Physics, Lanzhou University ＆ Institute of Modern Physics of CAS, Lanzhou 730000, China;Tokyo Kasei University, 1-18-1 Kaga, Itabashi, Tokyo 173-8602, Japan;Theoretical Research Division, Nishina Center, RIKEN, Wako, Saitama 351-0198, Japan)

机构地区：[1]湖南师范大学物理系,长沙410081 [2]中国科学院高能物理研究所,北京100049 [3]中国科学院大科学装置理论物理研究中心,北京100049 [4]兰州大学物理科学与技术学院,兰州730000 [5]兰州大学&中国科学院近代物理研究所强子与CSR物理研究中心,兰州730000 [6]Tokyo Kasei University,1-18-1 Kaga,Itabashi,Tokyo 173-8602,Japan [7]Theoretical Research Division,Nishina Center,RIKEN,ⅥkO,Saitama 351-0198,Japan

出　　处：《原子核物理评论》2018年第1期1-4,共4页Nuclear Physics Review

基　　金：国家自然科学基金资助项目(11475192,11305003,11222547,11175073,11447604,11705056,U1204115)

摘　　要：Λ_c+重子家族存在一个疑难,也就是重夸克有效理论预言的轨道角动量为L=2的多重态中的态在实验上是缺失的,而且已发现的Λ_c(2765)+和Λ_c(2940)+的JP量子数仍然未知。在本工作中,我们使用双夸克图像计算了重子的质量,研究了Λ_c(2765)+和Λ_c(2940)+的可能归类以及仍缺失的具有L=2和量子数的Λ_c+态,进而指出Λ_c(2880)+的峰结构中实际上已经包含了L=2、这一缺失态,并建议Λ_c(2765)+和Λ_c(2940)+的量子数应分别为2S(1/2+)和2P(1/2-)。There is a puzzle in the Λ＋ cfamily, i.e., one member with JP= 3/2＋is missing in a L =2 multiplet which the heavy quark effective theory predicts, and JP’s of Λ＋c（2765）＋and Λ_c（2940）are unknown. Using a light diquark picture to calculate baryon masses, we study possible assignments of two Λ_c’s with unknown JPand the missing Λ＋ cwith 3/2＋for L = 2, and we find the most probable possibility that the peak corresponding to Λ_c（2880）＋actually includes a missing member with spin 3/2＋for L = 2 and that quantum numbers of Λ_c（2765）＋and Λ_c（2940）＋are 2S（1/2＋） and 2P （1/2-）, respectively.

关 键 词：Λc家族 相对论夸克模型 对夸克 

分 类 号：O572.33[理学—粒子物理与原子核物理]