Sub-threshold production of K0s mesons and Λ hyperons in Au(1.23A GeV)+Au

We present first data on sub-threshold production of K0s mesons and Λ hyperons in Au+Au collisions at √sNN = 2.4 GeV. We observe an universal scaling of hadrons containing strangeness, independent of their corresponding production thresholds. Comparing the yields, their part> scaling, and the shapes of the rapidity and the pt spectra to state-of-the-art transport model (UrQMD, HSD, IQMD) predictions, we find that none of the latter can simultaneously describe all observables with reasonable χ2 values.