3-CHANNEL MODEL OF MESON-MESON SCATTERING AND SCALAR MESON SPECTROSCOPY

New solutions on the scalar-isoscalar pi pi phase shifts are analysed together with previous K (K) over bar results using a separable potent ial model of three coupled channels (pi pi, K (K) over bar and an effe ctive 2 pi 2 pi system). Model parameters are fitted to two sets of so lutions obtained in a recent analysis of the CERN-Cracow-Munich measur ements of the pi(-)P(up arrow) --> pi(+)pi(-)n reaction on a polarized target. A relatively narrow (90-180 MeV) scalar resonance f(0)(1400-1 460) is found, in contrast to a much broader(Gamma approximate to 500 MeV) state emerging from the analysis of previous unpolarized target d ata. (C) 1997 Elsevier Science B.V.