Strange particle measurements at the CERN SPS – NA49 and NA61/SHINE experiments

Strangeness production in heavy-ion collisions has always been an important observable for probing the state of matter created in these collisions. In particular, relative strangeness production, its event-by-event fluctuations as well as their dependence on the collision energy and centrality are sensitive probes of the deconfinement phase transition. This contribution presents selected NA49 and NA61/SHINE results on strangeness production in central Pb + Pb collisions and p + p interactions in the SPS energy range. Special attention is given to data on particle ratios and ratio fluctuations as well as image, image resonance production.