Proton induced K+ production and the s anti-s content of the proton

We investigate the exclusive proton-induced K+ production near the kaon threshold. Compared are two models: a meson-exchange model, which includes π, ρ, K and K* exchange, together with the dominant baryon resonances, and a quark-gluon model, where momentum sharing is provided via the exchange of two gluons. Based on covariant bound state wave functions for the meson and the baryons - which we treat as quark-diquark objects - first results for the pp→ pΛK+ total cross section are presented for both models. (author)