Kaon pair production in proton-proton collisions at COSY-ANKE

The near-threshold production of kaon-pairs has been investigated in protonproton collisions at Cooler Synchrotron (COSY)at Forschungszentrum Jülich. In the pp → ppKK reaction, the invariant mass distributions of Kp, Kpp, and KK indicate the presence of both Kp and KK final state interactions. Total cross sections for pp → ppφ reaction have been determined at excess energies ε of 18.5, 34.5, and 76 MeV. The differential spectra at an excess energy of 18.5 MeV exhibit a clear s-wave dominance, while the high statics data at an excess energy of 76 MeV shows that higher partial waves represent the majority of the pp → ppφ total cross section, whose energy dependence would then seem to require some s-wave φp enhancement near threshold.