1−− and 0++ heavy four-quark and molecule states in QCD

We estimate the masses of the 1−− heavy four-quark and molecule states by combining exponential Laplace (LSR) and finite energy (FESR) sum rules known perturbatively to lowest order (LO) in αs but including non-perturbative terms up to the complete dimension-six condensate contributions. We use double ratio of sum rules (DRSR) for determining the SU(3) breakings terms. The SU(3) mass-splittings of about (50-110) MeV and the ones of about (250-300) MeV between the lowest ground states and their 1st radial excitations are (almost) heavy-flavour independent. The mass predictions summarized in Table 2 are compared with the ones in the literature (when available) and with the three Yc(4260,4360,4660) and Yb(10890)1−− experimental candidates. We conclude that the lowest observed state cannot be a pure1−− four-quark nor a pure molecule but may result from their mixings. We extend the above analyzes to the 0++ four-quark and molecule states which are about (0.5-1) GeV heavier than the corresponding 1−− states, while the splittings between the 0++ lowest ground state and the 1st radial excitation is about (300-500) MeV. We complete the analysis by estimating the decay constants of the 1−− and 0++ four-quark states. Our predictions can be tested using some alternative non-perturbative approaches or/and at LHCb or some other hadron factories.