Dissociation calculations forS-wave$Q^2 \bar Q^2$ systems

Abstract

We have examined the$c^2 \bar c^2$ system in the context of additive quark potential model using an extended variational ansatz for the multiquark wave function that includes both meson-meson component and the admixture of the four-quark confined states. The latter were shown to generate a mechanism for the short-range meson-meson interaction that can produce resonances or even bound states in the four-quark systems. A quantitative effect of this mechanism is studied for a model with harmonic oscillator confinement and for the “Coulomb plus linear” model. In both cases, we find the 2⁺⁺ resonance in the mass region 6.5–6.6 GeV with Γ=100−200 MeV, depending of the choice of the model parameters.