Sub-threshold production of K$^{0}_{s}$ mesons and ${\Lambda}$ hyperons in Au+Au collisions at $\sqrt{s_{NN}}$ = 2.4 GeV

Abstract We present first data on sub-threshold production of K s 0 mesons and Λ hyperons in Au+Au collisions at s NN = 2.4 GeV. We observe an universal 〈 A p a r t 〉 scaling of hadrons containing strangeness, independent of their corresponding production thresholds. Comparing the yields, their 〈 A p a r t 〉 scaling, and the shapes of the rapidity and the p t spectra to state-of-the-art transport model (UrQMD, HSD, IQMD) predictions, we find that none of them can simultaneously describe these observables with reasonable χ 2 values.