First measurement of the strange particles RCP nuclear modification factors in heavy-ion collisions at the SPS

The NA57 experiment has measured the pT distributions of KSO, Λ, and \(\bar \Lambda \) particles in fixed-target Pb−Pb interactions at √sNN=17.3 GeV, as a function of the collision centrality. In this paper we study the central-to-peripheral nuclear modification factors and compare them to other measurements and to theoretical predictions.