Bag model six-quark states and nucleon-nucleon scattering

The apparent overlap of the short-range region of asymptotic freedom of quarks with the long-range region of effective hadron clusters permits the application of R-matrix methods to hadron-hadron reactions. The f-matrix formalism is particularly suitable and extends the ideas of the P-matrix method. Applications of the latter indicate that transition region effects are important. This implies that the f-matrix conditions should be applied at somewhat smaller radii than that of the equilibrium bag in order that asymptotic freedom may be assumed. Application to the nucleon-nucleon system in 1S0 and 3S1 states shows that the original MIT bag model and a new bag model with negative-quark self-energies are inconsistent with the present data for laboratory energy E/sub L/ less than or equal to 800 MeV. The cloudy-bag model with a boundary at R = 0.9 fm is consistent with the data and predicts structure at about 2.7-GeV mass with well-defined signature in terms of width, inelasticity, and singlet-triplet splitting. The position of the structure is sensitive to the bag model assumptions. Many such structures are expected in hadron-hadron collisions at a few GeV that would enable the specification of several aspects of quark-gluon dynamics