phi and rho plus omega vector-mesons produced in lead-induced collisions

Abreu, M. C.; Alessandro, B.; Alexa, C.; Arnaldi, Roberta; Atayan, M.; Cbaglin,; Baldit, A.; Bedjidian, M.; Beole', Stefania; Boldea, V.; Bordalo, P.; Borenstein, S. R.; Borges, G.; Bussiere `, A.; Capelli, L.; Castor, J.; Castanier, C.; Chaurand, B.; Cheynis, B.; Chiavassa, Emilio Luciano; Cicalo`, C.; Claudino, T.; Comets, M. P.; Constans, N.; Constantinescu, S.; Cortese, P.; Cruz, J.; De Falco, A.; Dellacasa, Giuseppe; De Marco, N.; Devaux, A.; Dita, S.; Drapier, O.; Espagnon, B.; Fargeix, J.; Force, P.; Gallio, Mauro; Gavrilov, Y. K.; Gerschel, C.; Giubellino, P.; Golubeva, M. B.; Gonin, M.; Grigorian, A. A.; Grigorian, S.; Grossiord, J. Y.; Guber, F. F.; Guichard, A.; Gulkanyan, H.; Hakobyan, R.; Haroutunian, R.; Idzik, M.; Jouan, D.; Karavitcheva, T. L.; Kluberg, L.; Kurepin, A. B.; Le Bornec, Y.; Lourenc¸o, C.; Macciotta, P.; Mac Cormick, M.; Marzari Chiesa, A.; Masera, Massimo; Masoni, A.; Monteno, M.; Musso, A.; Petiau, P.; Piccotti, A.; Pizzi, J. R.; Prado da Silva, W. L.; Prino, F.; Puddu, G.; Quintans, C.; Ramello, Luciano; Ramos, S.; Rato Mendes, P.; Riccati, L.; Romana, A.; Santos, H.; Saturnini, P.; Scalas, E.; Scomparin, E.; Serci, S.; Shahoyan, R.; Sigaudo, F.; Ssilva,; Sitta, Mario; Sonderegger, P.; Tarrago, X.; Topilskaya, N. S.; Usai, G. L.; Vercellin, Ermanno; Villatte, L.; Willis, N.

doi:10.1088/0954-3899/28/7/335

The experiment NA50 studies the strangeness production by means of the BRphiμμσphi/(BRρμμσρ + BRωμμσω) cross-sections ratio in relativistic heavy ion collisions with respect to proton and light ion collisions. New results for Pb+Pb interactions at 158 A GeV/c are presented (1998 data) and analysed with a different method. The BRphiμμσphi/(BRρμμσρ + BRωμμσω) ratio shows an increase with the number of participants, in agreement with previous results. The inverse slope parameter extracted from the MT universal scaling is also studied.