Where and what are the scalar mesons

A self-consistent analysis of the J/sup C/P = 0++ partial waves obtained from high-statistics Kπ, KK-bar, and ππ data has been performed to verify the existence and to determine the resonance parameters of the I = 1/2 and I < 0 scalar mesons. A mass-dependent parametrization of the Kπ partial wave yields one and only one strange scalar meson, the kappa (1510), with a width of several hundred MeV. Isoscalar 0++ mesons found in simultaneous fits to KK-bar and ππ data are the epsilon (800), S* (1005), and epsilon' (1540) with widths of about l000, 8, and 200 MeV, respectively. No simple interpretation of all these states and the delta (980) and possible delta' (1300) as qq-bar mesons, qq-barqq-bar bound states, or gluon-gluon bound states exists. Possible candidates for an SU(3) nonet of qq-bar states are found to be (a) epsilon (800), epsilon' (1540), sigma (980), and kappa (1540) or (b) S* (1005), epsilon' (1540), sigma' (1300), and kappa