ϕ, ρ andω production in collisions induced by deuteron and heavy ions at 200 A GeV/c

The production of low mass dimuons has been measured in d-C, d-U and S-U collisions at 200 GeV per nucleon, and in Pb-Pb collisions at 160 GeV per nucleon. Theϕ, ρ andω productions in S-U collision [1, 2] are extracted from a new set of data with increased statistic, and are throughϕ/(ω+ρ) ratio compared to first results on deuteron induced production. These new analyses are presented in the limitedM T domain of recent Pb-Pb measurement whose preliminary results are also presented.