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Associated strangeness production was studied in the pp ! ! p + p reaction at the CERN antiproton facility LEAR using the experimental setup of PS185. Results from two high{statistics measurements at incident a n tiproton momenta of 1:642 and 1.918 GeV/c are reported. Approximately 40 000 reconstructed events at each momentum have allowed us to measure the total and dierential cross-sections, the spin polarizations, the spin correlations, and the singlet fractions of the pair. Since the decays of both the and the w ere simultaneously observed in the same detector, we are able to provide upper limits on CP and CPT violation phenomena in the weak interaction.

The isoscalar giant monopole resonance in the nucleus Mg was investigated by inelastic Li scattering at EL;=156 MeV. At extreme forward angles fragmented EO strength was observed up to E =23 MeV. The extracted strength centered at 18.3~0.5 MeV excitation energy with a width of I =4.8~0.5 MeV corresponds to 97.3%~15% of the EO energy weighted sum rule. PACS number(s): 24.30.Cz, 25.70.Bc, 25.70.Ef, 27.30.+t

The ( Li, He) reaction was studied on targets of "C, "0, ' Mg, and 'Ca at a beam energy of 156MeV. Zero degree measurements of all systems are presented. The evaluated cross sections for Gamow-Teller transitions at 8=0' and the corresponding strengths of analogous beta decays are compared.

The reactionpp →ΛΛ →pπ + pπ − has been measured with high statistics at a beam momentum of pp = 1.637 GeV/c. The use of a transversely-polarized frozen-spin target combined with the self-analyzing property of Λ/Λ decay allows access to unprecedented information on the spin structure of the interaction. The most general spin-scattering matrix can be written in terms of eleven real parameters for each bin of scattering angle, each of these parameters is determined with reasonable precision. From these results all conceivable spin-correlations are determined with inherent self-consistency. Good agreement is found with the few previously existing measurements of spin observables inpp →ΛΛ near this energy. Existing theoretical models do not give good predictions for those spin-observables that had not been previously measured.