X(3872) Revisited: The Roles of OPEP and the Quark Degrees of Freedom

The X(3872) is investigated by employing the quark-hadron hybrid model, that consists of the $$c\bar{c}$$ core, $$D^{(*)}\bar{D}{}^*$$ , $$J/\psi \omega $$ , and $$J/\psi \rho $$ two-meson states. Due to the attraction from the $$c\bar{c}$$ - $$D\bar{D}{}^*$$ coupling and from the OPEP tensor coupling, a very thin peak can appear at the $$D^{0}\bar{D}{}^{*0}$$ threshold. The energy of the corresponding pole of the scattering matrix is $$E=+0.06-0.14i$$ MeV, which is on the physical sheet and above the threshold, the same as the one of the poles from the LHCb data analysis.