A further study of the centrally produced π+π− and π+π−π+π− channels in pp interactions at 300 and 450 GeV/c

Abstract An analysis of the centrally produced π + π − and π + π − π + π − mass spectra from the WA76 and WA91 experiments is presented, which shows that in the π + π − π + π − channel there are two new states, the f 0 (1450) and f 2 (1900). There is another new state in the π + π − channel with M = 1497 ± 30 MeV and Γ = 199 ± 30 MeV, which is compatible with the f 0 (1520) observed by the Crystal Barrel experiment. Another interpretation is discussed, where the 1450 and 1497 GeV structures are explained as being due to an interference effect between the f 0 (1365) and f 0 (1520).