Strangeness measurements at the HADES experiment

Abstract\nWe report on HADES measurements of strange hadrons in the collision systems Ar(1.756 AGeV)+KCl and p+p at 3.5 GeV. Comparisons of K 0 s transverse mass and rapidity spectra to IQMD transport model calculations give a strong hint to a repulsive kaon-nucleon potential. The effect of the potential shows up strongest at very low transverse momenta, which were measured by HADES with high statistics. Statistical model fits show a fair agreement to the particle yields measured in the heavyion data, apart from the ? ? yield which is off by more than an order of magnitude. Furthermore, first results from the ?(1385) + reconstruction in p+p reactions are presented, showing an excellent agreement with published data.