Hyperon production in 40 A GeV/c collisions from the NA57 experiment

Enhancements of strange baryon and anti-baryon yields were first observed in Pb–Pb interactions at 160 A GeV/c by WA97. The aim of the NA57 experiment is to investigate how these enhancements behave as a function of energy, and over a broader centrality range than that which was available with WA97. This paper presents a comparison of the hyperon yields in Pb–Pb interactions at 40 A GeV/c and 160 A GeV/c. Preliminary signals for the p-Be data at 40 A GeV/c are also shown.