An improved understanding of nonperturbative QCD can be obtained by the recently developed soft color interaction models. Their essence is the variation of color string-field topologies, giving a unified description of final states in high energy interactions, e.g., diffractive and nondiffractive events in $\mathrm{ep}$ and $p\overline{p}.$ Here we present a detailed study of such models (the soft color interaction model and the generalized area law model) applied to $p\overline{p},$ considering also the general problem of the underlying event including beam particle remnants. With models tuned to DESY HERA $\mathrm{ep}$ data, we find a good description also of Fermilab Tevatron data on production of W, beauty and jets in diffractive events defined either by leading antiprotons or by one or two rapidity gaps in the forward or backward regions. We also give predictions for diffractive $J/\psi$ production where the soft exchange mechanism produces both a gap and a color singlet $c\overline{c}$ state in the same event. This soft color interaction approach is also compared with Pomeron-based models for diffraction, and some possibilities to experimentally discriminate between these different approaches are discussed.

• Received 25 June 2001

DOI:https://doi.org/10.1103/PhysRevD.64.114015