Production of the doubly strange H dibaryon

There is much current interest in the spectroscopy of multiquark states. Predictions abound for the existence of baryonium (Q/sup 2/ anti Q/sup 2/) and six-quark dibaryon (Q/sup 6/) resonances, for instance. In the strangeness S = -2 sector of Q/sup 6/, the MIT bag model predicts a dibaryon H with quantum numbers J/sup ..pi../ = 0/sup +/, isospin I = 0, and mass M/sub H/ approx. = 2150 MeV approx. = 2M/sub ..lambda../ -80 MeV. The H has quark composition uuddss, so all quarks can occupy the ls state; it is unique in that it possesses no strong decay modes. The fact that the H mass is considerably below the ..lambda lambda.. or XiN thresholds precludes its interpretation as a deuteron-like object bound by conventional long-range meson exchange forces. The H has been searched for in the reaction p + p ..-->.. K/sup +/ + K/sup +/ + H by Carroll et al., with an upper limit of about 100 nb/sr/sup 2/ for two K/sup +/'s at +- 18/sup 0/ in the lab system. Some crude cross section estimates we have made for this process indicate much smaller cross sections than this limit. A more natural way to produce the H, in our view, is via the (K/sup -/, K/sup +/) reaction on a diproton in a nuclear target, i.e. K/sup -/ + (pp) ..-->.. K/sup +/ + H