  We study how the scalar f_0(980) and a_0(980) states are produced in the
two-photon collisions and radiative decays of the phi meson through unitarized
Born amplitudes with the charged pion and kaon loops followed by S-wave
meson-meson scattering amplitudes. We found in a previous paper that f_0(980)
is generated as the bound state resonance, but a_0(980) as the cusp, and find
herre that the nature of the generation of both states is consistent with the
features of the production processes.

High Energy Physics - Phenomenology