Associate K0 production in p+p collisions at 3.5 GeV: The role of Δ(1232)++

An exclusive analysis of the 4-body final states Λ+p+π+K0 and Σ0+p+π++K0 measured with HADES for p+p collisions at a beam kinetic energy of 3.5 GeV is presented. The analysis uses various phase space variables, such as missing mass and invariant mass distributions, in the four particle event selection (p, π+, π+, π-) to find cross sections of the different production channels, contributions of the intermediate resonances Δ++ and Σ(1385)+ and corresponding angular distributions. A dominant resonant production is seen, where the reaction Λ+Δ+++K0 has an about ten times higher cross section (29.45 ±0.08 +1.67-1.46 ±2.06 μb) than the analougous non-resonant reaction (2.57 ±0.02 +0.21-1.98 ±0.18 μb). A similiar result is obtained in the corresponding Σ0 channels with 9.26 ±0.05 +1.41-0.31 ±0.65 μb in the resonant and 1.35 ±0.02 +0.10-1.35 ±0.09 μb in the non-resonant reactions.