Taylor’s Series and Dispersion Relation Analyses of the Vector Pion Form Factor and their Comparison with Perturbative and Non Perturbative Calculations
نویسنده
چکیده
The first three coefficients of the Taylor’s series expansion of the vevtor pion form factor as a function of the momentum transfer are evaluated using the experimental data on the pion form factor and the P-wave ππ phase shifts. The real part of the form factor as a function of energy is also calculated by dispersion relation. Comparisons there results with Chiral Perturbation Theory and unitarized models are given. ∗unité propre 014 du CNRS
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