Strange particle production in p+p, p+Pb and Pb+Pb interactions from NA49

Abstract

Recent NA49 results on Λ, , Ξ− and + production in minimum-bias p+p and centrality-selected p+Pb collisions at 158 GeV/c, and the results on Λ, , K+ and K− production in central Pb+Pb collisions at 40, 80 and 158 A GeV are discussed and compared with other available data. By comparing the energy dependence of Λ and production at mid-rapidity a striking similarity is observed between p+p and A+A data. This is also seen in the energy dependence of the Λ/π ratio. K+/π at mid-rapidity is affected in a similar way, due to the associated production of K+ together with Λ particles. The observed yields increase faster than the number of wounded nucleons when comparing p+Pb to p+p. As already observed in A+A collisions, the increase is larger for multistrange than for strange baryons and for baryons than for anti-baryons.