News on strangeness production from the NA61/SHINE experiment

Abstract

Strangeness production in high-energy hadronic and nuclear collisions continues to be one of the central topics in the study of strongly interacting matter. The data collected by the NA61/SHINE experiment at the CERN SPS North Area allow for a comprehensive scan of the strangeness production across various collision energies and system sizes. This article focuses on the new results of the strangeness production in central collisions of medium-sized nuclei, such as Ar+Sc, at the SPS energy range. In particular, the results for Lambda hyperons and charged and neutral $K$ mesons are shown. The energy and system size dependencies of Lambda-to-pion and strangeness-to-pion ratios are also explored. Moreover, an unexpected excess of charged over neutral $K$ meson production in Ar+Sc and $\pi^-$+C interactions is presented. The obtained results are compared with predictions from selected particle production models, as well as with existing world data from proton-proton and nucleus-nucleus collisions.