K ¯ K Scattering Amplitude to One Loop in Chiral Perturbation Theory, Its Unitarization and Pion Form Factors
نویسنده
چکیده
We have calculated the KK̄ → KK̄ scattering amplitude to next to leading order in Chiral Perturbation Theory. Then, making use of a unitarization procedure with one or several coupled channels (ππ,KK̄ in our case) we have calculated the ππ → ππ, ππ → KK̄ and KK̄ → KK̄ S and P waves in good agreement with the experiment up to √ s ≃ 1.2 GeV. The ππ scattering lengths with isospin and spin (I,J) equal to (0,0), (1,1) and (2,0) are also calculated in agreement with experiment and former Chiral Perturbation Theory calculations. Finally we have employed these amplitudes, making use of an Omnès representation, to calculate the scalar and the vector pion form factors, obtaining a good agreement with the available experimental data. PACS numbers: 12.39.Fe,13.75.Lb, 13.40.Gp, 11.80.Gw
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