Analysis of the tetraquark and hexaquark molecular states with the QCD sum rules

作     者：Zhi-Gang Wang Zhi-Gang Wang

作者机构：Department of PhysicsNorth China Electric Power UniversityBaoding 071003China 

出 版 物：《Communications in Theoretical Physics》 (理论物理通讯（英文版）)

年 卷 期：2021年第73卷第6期

页      面：80-93页

核心收录：

学科分类：07[理学] 070202[理学-粒子物理与原子核物理] 0702[理学-物理学] 

基　　金：supported by National Natural Science Foundation Grant Number 11775079 

主　　题：tetraquark molecular states hexaquark molecular states QCD sum rules 

摘      要：In this article,we construct the color-singlet-color-singlet type currents and the color-singlet-colorsinglet-color-singlet type currents to study the scalar D*■*,D*D*tetraquark molecular states and the vector D*D*■*,D*D*D*hexaquark molecular states with the QCD sum rules in *** calculations,we choose the pertinent energy scales of the QCD spectral densities with the energy scale formula■for the tetraquark and hexaquark molecular states respectively in a consistent *** obtain stable QCD sum rules for the scalar D*■*,D*D*tetraquark molecular states and the vector D*D*■*hexaquark molecular state,but cannot obtain stable QCD sum rules for the vector D*D*D*hexaquark molecular *** connected(nonfactorizable)Feynman diagrams at the tree level(or the lowest order)and their induced diagrams via substituting the quark lines make positive contributions for the scalar D*D*tetraquark molecular state,but make negative or destructive contributions for the vector D*D*D*hexaquark molecular *** is of no use or meaningless to distinguish the factorizable and nonfactorizable properties of the Feynman diagrams in the color space in the operator product expansion so as to interpret them in terms of the hadronic observables,we can only obtain information about the short-distance and long-distance contributions.