A discussion on the anomalous threshold enhancement of J/ψ–ψ(3770)couplings and X(6900)peak  

作　　者：陆业 陈畅 秦广友 郑汉青 Ye Lu;Chang Chen;Guang-You Qin;Han-Qing Zheng(Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics(MOE),Central China Normal University,Wuhan 430079,China;Department of Physics,Peking University,Beijing 100871,China;College of Physics,Sichuan University,Chengdu 610065,China)

机构地区：[1]Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics(MOE),Central China Normal University,Wuhan 430079,China [2]Department of Physics,Peking University,Beijing 100871,China [3]College of Physics,Sichuan University,Chengdu 610065,China

出　　处：《Chinese Physics C》2024年第4期1-5,共5页中国物理C（英文版）

基　　金：Supported in part by the National Nature Science Foundations of China (12335002);the Fundamental Research Funds for the Central Universities。

摘　　要：The attractive interaction between J/ψandψ(3770)has to be strong enough if X(6900)is of the molecule type.We argue that sinceψ(3770)decays predominantly into a DD^(¯)pair,the interactions between J/ψandψ(3770)may be significantly enhanced owing to the three point DD^(¯)loop diagram.The enhancement originates from the anomalous threshold located at t=−1.288 GeV^(2),whose effect propagates into the s-channel partial wave amplitude in the vicinity of √s≃6.94 GeV.This effect may be helpful in the formation of the X(6900)peak.

关 键 词：exotic hadrons hadron molecule X(6900) 

分 类 号：O572.2[理学—粒子物理与原子核物理]