X(3872), IG(JPC) = 0+(1++), As the Χc1(2p) Charmonium

Contrary to almost standard opinion that the [Formula: see text]) resonance is the [Formula: see text] molecule or the [Formula: see text] four-quark state, we discuss the scenario where the [Formula: see text] resonance is the [Formula: see text] charmonium which “sits on” the [Formula: see text] threshold. We explain the shift of the mass of the [Formula: see text] resonance with respect to the prediction of a potential model for the mass of the [Formula: see text] charmonium by the contribution of the virtual [Formula: see text] intermediate states into the self energy of the [Formula: see text] resonance. This allows us to estimate the coupling constant of the [Formula: see text] resonance with the [Formula: see text] channel, the branching ratio of the [Formula: see text] decay, and the branching ratio of the [Formula: see text] decay into all non-[Formula: see text] states. We predict a significant number of unknown decays of [Formula: see text] via two gluon: [Formula: see text]. We suggest a physically clear program of experimental researches for verification of our assumption.