Study of the $K^+K^-$ Final State Interaction in Proton--Proton and Electron--Positron Collisions

Near Threshold KK Meson-Pair Production in Proton-Proton Collisions

The near threshold total cross section and angular distributions of KK pair production via the reaction pp −→ ppKK have been studied at an excess energy of Q = 17 MeV using the COSY-11 facility at the cooler synchrotron COSY. The obtained cross section as well as an upper limit at an excess energy of Q = 3 MeV represent the first measurements on the KK production in the region of small excess e...

Proton - Electron - Positron Design Study

Exclusive Diffractive Final States in Electron-proton Collisions

The diffractive scattering is a process where the colliding particles scatter at very small angles and without any color flux in the final state. This involves a propagator carrying the vacuum quantum numbers, called Pomeron and described, in the soft regime, within the Regge theory. The discovery of a big amount of diffractive events in DIS regime provided a hard scale which can be varied over...

Final State Interactions in the Near-Threshold Production of Kaons from Proton-Proton Collisions

We analyse the pp → pΛK cross section recently measured at COSY arguing that the enhancement of the production cross section at energies close to the reaction threshold should be due to the Λp final state interaction. We find that the experimental Λp elastic scattering data as well as the predictions from the Jülich-Bonn model are in reasonable agreement with the new results on K-meson producti...

Charm in Electron–proton Collisions

Charm in electron–proton collisions is a particularly large and interesting field. For this summary two topics particularly relevant for HERA have been selected. First the study of inelastic J/ψ production in both the photoproduction and the electroproduction regime, study still needed to clarify the J/ψ production mechanisms. Second the analysis of D photoproduction events, study than can lead...