Bound-state problem of the [Formula Presented] and [Formula Presented] systems

We used the [Formula Presented] and [Formula Presented] potentials derived from the chiral quark cluster model to analyze the bound-state problem of the [Formula Presented] and [Formula Presented] systems when the two-body subsystems can be in S-wave states. We found that the [Formula Presented] system has only one bound state right at the [Formula Presented] threshold while for the [Formula Presented] system there are no bound-state solutions in any of the allowed channels, although a couple of them are nearly bound. Our model predicts the [Formula Presented] resonance as being a bound state of the [Formula Presented] system at the [Formula Presented] threshold.