Towards the understanding of fully-heavy tetraquark states from various models

We use a color-magnetic interaction model (CMIM), traditional constituent quark (CQM) and multiquark color flux-tube (MCFTM) to systematically investigate the properties of states $[Q_1Q_2][\bar{Q}_3\bar{Q}_4]$ ($Q=c,b$). The dynamical investigation indicates that CMIM can not completely absorb QCD effects through effective mass overestimates in under assumption same spatial configurations. Coulomb plays critical role calculations on heavy hadrons, which induces fact none bound be found models. configuration $\left[[Q_1Q_2]_{\mathbf{6}_c}[\bar{Q}_3\bar{Q}_4]_{\bar{\mathbf{6}}_c}\right]_{\mathbf{1}}$ should taken seriously ground due strong attraction between $[Q_1Q_2]_{\mathbf{6}_c}$ $[\bar{Q}_3\bar{Q}_4]_{\bar{\mathbf{6}}_c}$. $\left[[Q_1Q_2]_{\bar{\mathbf{3}}_c}[\bar{Q}_2\bar{Q}_4]_{\mathbf{3}_c}\right]_{\mathbf{1}}$ is absolutely dominant excited because within $[Q_1Q_2]_{\bar{\mathbf{3}}_c}$ $[\bar{Q}_2\bar{Q}_4]_{\mathbf{3}_c}$. $J/\Psi$-pair resonances recently observed by LHCb are difficult accommodated CMIM. broad structure ranging from 6.2 6.8 GeV described as tetraquark state $[cc][\bar{c}\bar{c}]$ various narrow $X(6900)$ identified with $L=1$ ($L=2$) CQM (MCFTM).