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Dispersion Relation Analyses of Pion Form Factor, Chiral Perturbation Theory and Unitarized Calculations

Tran N. Truong
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Abstract

The Vector Pion form factor below 1 GeV is analyzed using experimental data on its modulus, the P-wave pion pion phase shifts and dispersion relation. It is found that causality is satisfied. Using dispersion relation, terms proportional to s squared and s cubed are calculated using the experimental data, where s is the momentum transfer. They are much larger than the one-loop and two-loop Chiral Perturbation Theory calculations. Unitarized model calculations agree very well with dispersion relation results.

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Tran N. Truong. 2000-04-21. Dispersion Relation Analyses of Pion Form Factor, Chiral Perturbation Theory and Unitarized Calculations. https://arxiv.org/abs/hep-ph/0001271

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