Analysis of pion electromagnetic form factor by the dispersion relation with QCD constraint
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چکیده
The pion electromagnetic form factor is investigated by using the dispersion relation with the superconvergence condition, which was proposed to synthesize the vector meson dominance model and QCD. The absorptive part is given as an addition of the resonance and the QCD terms, the latter being parametrized so as to realize the prediction of perturbative QCD. The experimental data are analyzed and the parameters for the QCD part, the resonance part as well, are determined. Existing experiments for the form factor are reproduced very well both for the space-like and time-like momenta. PACS 11.55.Fv Dispersion relations PACS 12.38.Aw General properties of QCD (dynamics confinement, etc.) PACS 13.40Gp Electromagnetic form factor.
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تاریخ انتشار 2001