Study of the transverse mass spectra of strange particles in Pb–Pb collisions at 158 A GeV/c

The NA57 Collaboration,; Antinori, Federico; Bacon, P.; Badalà, 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.; Divià, 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.; Králik, I.; Krav áková, A.; Kuijer, P.; Lenti, V.; Lietava, R.; Løvhøiden, G.; Manzari, V.; Martinská, G.; Mazzoni, M. A.; Meddi, F.; Michalon, A.; Morando, Maurizio; Nappi, E.; Navach, F.; Norman, P. I.; Palmeri, A.; Pappalardo, G. S.; Pastir ák, B.; Pi út, J.; Pi útová, N.; Platt, R. J.; Posa, F.; Quercigh, E.; Riggi, F.; Röhrich, D.; Romano, G.; afa ík, K.; Ándor, L.; Schillings, E.; Segato, Gianfranco; Sené, M.; Sené, R.; Snoeys, W.; Soramel, Francesca; Spyropoulou Stassinaki, M.; Staroba, P.; Toulina, T. A.; Turrisi, R.; Tveter, T. S.; Urbán, 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.; Vrláková, J.; Závada, P.

doi:10.1088/0954-3899/30/6/011

The NA57 experiment has collected high statistics, high purity samples of K-S(0) and Lambda, Xi and Omega hyperons produced in Pb-Pb collisions at 158 A GeV/c. In this paper we present a study of the transverse mass spectra of these particles for a sample of events corresponding to the most central 53% of the inelastic Pb-Pb cross-section. We analyse the transverse mass distributions in the framework of the blast-wave model for the full sample and, for the first time at the SPS, as a function of the event centrality.