Lambda production in central Pb + Pb collisions at CERN-SPS energies

In this paper we present recent results from the NA49 experiment for A and Λ hyperons produced in central Pb+Pb collisions at 40, 80 and 158 A GeV. Transverse mass spectra and rapidity distributions for A are shown for all three energies. The shape of the rapidity distribution becomes flatter with increasing beam energy. The multiplicities at mid-rapidity as well as the total yields are studied as a function of collision energy including AGS measurements. The ratio Λ/π at mid-rapidity and in 4π has a maximum around 40 A GeV. In addition, Λ rapidity distributions have been measured at 40 and 80 A GeV, which allows us to study the A/A ratio.