Results from CERN WA97/NA57 Experiment on Strange Baryon Production in Pb-Pb Collisions

The CERN WA97 and NA57 experiments have been designed to study strange and multistrange particle production in Pb-Pb interactions at SPS energies. The strange baryon and antibaryon enhancements in Pb-Pb with respect to proton induced reactions, first observed by WA97 at 160 A GeV/c beam momentum, nicely fit with the expectations for the formation of a deconfined state of matter in relativistic heavy ion collisions. The results on the experimental program performed by its successor, NA57, to investigate the onset of deconfinement are presented.