Meson pair production in two-photon processes

The amplitudes γγ→ππ and ππ→Kanti K were investigated by performing a coupled-channel calculation of the final-state interactions in these processes which play a crucial role in reactions like e+e-→e+e-ππ (or Kanti K). Among the most interesting results it is found that the S* effect shows up very clearly in these reactions, and that there is an important enhancement in the I=0 s-wave amplitudes in a large energy range, from threshold to 1.5 GeV, which leads to the prediction of abundant π0π0 production in such reactions. Some comments on the general treatment of final-state interactions are also made. (Auth.)