A new high precision measurement of the reaction pp -> pK+Lambda at a beam momentum of 2.95 GeV/c with more than 200,000 analyzed events allows a detailed analysis of differential observables and their inter-dependencies. Correlations of the angular distributions with momenta are examined. The invariant mass distributions are compared for different regions in the Dalitz plots. The cusp structure at the N Sigma threshold is described with the Flatt\'e formalism and its variation in the Dalitz plot is analyzed.
The reaction $ pp\to pp\bf \omega$ was investigated with the TOF spectrometer, which is an external experiment at the accelerator COSY (Forschungszentrum Julich, Germany). Total as well as differential cross sections were determined at an excess energy of $93 MeV$ ($p_{beam}=2950 MeV/c$). Using the total cross section of $(9.0\pm 0.7 \pm1.1) \mu b$ for the reaction $ pp\to pp\omega$ determined here and existing data for the reaction $pp\to pp\bf \phi$, the ratio $\mathcal{R}_{\phi/\omega}=\sigma_\phi/\sigma_\omega$ turns out to be significantly larger than expected by the Okubo-Zweig-Iizuka (OZI) rule. The uncertainty of this ratio is considerably smaller than in previous determinations. The differential distributions show that the $\omega$ production is still dominated by S-wave production at this excess energy, however higher partial waves clearly contribute. A comparison of the measured angular distributions for $\omega$ production to published distributions for $\phi$ production at $83 MeV$ shows that the data are consistent with an identical production mechanism for both vector mesons.
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