Scalar Mesons within a model for all non-exotic mesons
  We describe a four-parameter model for non-exotic meson-meson scattering, which accommodates all non-exotic mesons, hence also the light scalar mesons, as resonances and bound states characterised by complex singularities of the scattering amplitude as a function of the total invariant mass. The majority of the full $S$-matrix mesonic poles stem from an underlying confinement spectrum. However, the light scalar mesons K0*(830), a0(980), f0(400-1200), and f0(980) do not, but instead originate in 3P0-barrier semi-bound states.   In the case of bound states, wave functions can be determined. For ccbar and bbbar, radiative transitions have been calculated. Here we compare the results to the data. 
Eef van Beveren (Univ.Coimbra, Portugal) and George Rupp (IST, Lisboa,   Portugal)