Analysis of the pion form factor in the space-like and time-like region

We discuss an analytic parametrization of the pion form factor which is only weakly model dependent. Its model dependence comes from a preference of those analytic functions that are smooth in a certain well-defined sense. Different solutions for different values of chi2 corresponding to different degrees of smoothness can be constructed. All available space-like and time-like data are taken into account simultaneously. Our approach allows conclusions on an incompatibility of space-like with time-like data sets and on the significance of the occurrence of higher coupled resonances. We discuss the asymptotic behaviour which is consistent with QCD and give the relevant low energy and resonance parameters. (orig.)