Observation of $\mth{K^+d}$ correlations from $\mth{pA}$ collisions

Results of a first experiment on (K(+)p) and (K(+)d) correlations from proton-carbon (pC) and proton-deuteron (pd) interactions,at beam energies above and much below the threshold for elementary kaon production in nucleon-nucleon reactions (T-NN = 1580 MeV) are discussed. These data, obtained with the ANKE spectrometer at COSY-Julich, provide first direct evidence for K+ production via the two-step mechanism and an indication for a cluster mechanism. It is shown that both processes contribute significantly in pC collisions at 1200 MeV, while they are strongly suppressed at 2300 MeV and also in pd-interactions at 1344 MeV. It is emphasized that the underlying kinematics can be exploited to distinguish between these reaction mechanisms.