Pion and kaon vector form factors and their role in π decay and the anomalous magnetic moment of the muon Original Research Article

The pion and kaon coupled-channel vector form factors are described by making use of the resonance chiral Lagrangian results together with a suitable unitarization method in order to take care of the final state interactions. A very good reproduction of experimental data is accomplished for the vector form factors up to √s ⩽ 1.2 GeV. We then apply these form factors to calculate the width of τ decay to two pions and to two kaons and also to evaluate the contribution of these mesons to the anomalous magnetic moment of the muon.