Photoproduction of ππ and K anti(K) pairs

S-wave photoproduction of π+π- and K+K- pairs on hydrogen is studied. Coupled channel final state interactions between different pseudoscalar mesons are included. Effective mass and momentum transfer distributions as well as total cross sections are calculated. Effective mass distributions in the Born approximation are structureless but the final state interactions produce peaks and dips near the energies corresponding to the scalar resonances f0(980) and f0(1400). Calculations are performed in the effective mass region between the ππ threshold and 1.6 GeV in the range of the momentum transfer squared up to 2 (GeV/c)2. The photon energy dependence of the total cross sections is studied between 2 and 15 GeV. Valuable information on the f0(980) resonance structure can be extracted from data. These calculations are closely related to the experimental program of the CEBAF accelerator in USA. (author)