Results on 40 A GeV/c Pb - Pb collisions from the NA57 experiment

Antinori, F.; Bacon, P.; Badal, A.; Barbera, R.; Belogianni, A.; Bhasin, A.; Bloodworth, I. J.; Bombara, M.; Bruno, G. E.; Bull, S. A.; Caliandro, R.; Campbell, M.; Carena, W.; Carrer, N.; Clarke, R. F.; Dainese, A.; DE HAAS, A. P.; DE RIJKE, P. C.; DI BARI, D.; DI LIBERTO, S.; Divi, R.; Elia, D.; Evans, D.; Feofilov, G. A.; Fini, R. A.; Ganoti, P.; Ghidini, B.; Grella, G.; Helstrup, H.; Hetland, K. F.; Holme, A. K.; Jacholkowski, A.; Jones, G. T.; Jovanovic, P.; Jusko, A.; Kamermans, R.; Kinson, J. B.; Knudson, K.; Kolozhvari, A. A.; Kondratiev, V.; Krlik, I.; Kravckov, A.; Kuijer, P.; Lenti, V.; Lietava, R.; Lvhiden, G.; Manzari, V.; Martinsk, G.; Mazzoni, M. A.; Meddi, F.; Michalon, A.; Morando, Maurizio; Nappi, E.; Navach, F.; Norman, P. I.; Palmeri, A.; Pappalardo, G. S.; Pastirck, B.; Pist, J.; Pistov, N.; Platt, R. J.; Posa, F.; Quercigh, E.; Riggi, F.; Rhrich, D.; Romano, G.; Safark, K.; Sndor, L.; Schillings, E.; Segato, Gianfranco; Sen, M.; Sen, R.; Snoeys, W.; Soramel, Francesca; SPYROPOULOU STASSINAKI, M.; Staroba, P.; Toulina, T. A.; Turrisi, R.; Tveter, T. S.; Urbn, J.; Valiev, F. F.; VAN DEN BRINK, A.; VAN DE VEN, P.; VANDE VYVRE, P.; VAN EIJNDHOVEN, N.; VAN HUNEN, J.; Vascotto, A.; Vik, T.; VILLALOBOS BAILLIE, O.; Vinogradov, L.; Virgili, T.; Votruba, M. F.; Vrlkov, J.; Zvada, P.

ABSTRACT The NA57 experiment has been designed to study the onset of the strange baryon and antibaryon enhancements in Pb-Pb with respect to p-Be collisions, first observed by WA97 at 160 A GeV/c. NA57 has extended the WA97 measurements to investigate the evolution of strangeness enhancement over a wider centrality range and as a function of the beam energy. Results on hyperon production in central Pb-Pb collisions at 40 A GeV/c are presented and compared with those obtained at higher energy, in the same centrality range.