Kaon pair production in pp, pd and dd collisions at COSY

The near-threshold production of kaon-pairs has been investigated in proton-proton, proton-deuteron and deuteron-deuteron collisions at the Cooler Synchrotron COSY. The excitation function for the pp -> ppK(+)K(-) reaction and the invariant K(-)p, K(-)pp, and K+K- mass distributions indicate the presence of both K(-)p and K+K- final state interactions. Analogous final-state interactions of antikaons with deuterons has been found in the pp -> dK(+)(K) over bar (0) reaction as well as in the pn -> d K+K- reaction, measured in the quasi-free pd -> p(sp)dK(+)K(-) process with a "spectator" proton (p(sp)). The existing COSY data on the pd -> (HeK+K-)-He-3 reaction are not yet sufficient to study the K-3He and K+K- final state interactions. A very small total cross section was found for the dd -> (HeK+K-)-He-4 reaction.