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A Critical Examination to the Unitarized $ππ$ Scattering Chiral Amplitudes

Qin Ang·Zhiguang Xiao·H. Zheng·X. C. Song
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Abstract

We discuss the Padé approximation to the $ππ$ scattering amplitudes in 1--loop chiral perturbation theory. The approximation restores unitarity and can reproduce the correct resonance poles, but the approximation violates crossing symmetry and produce spurious poles on the complex $s$ plane and therefore plagues its predictions on physical quantities at quantitative level. However we find that one virtual state in the IJ=20 channel may have physical relevance.

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Qin Ang, Zhiguang Xiao, H. Zheng, X. C. Song. 2001-09-02. A Critical Examination to the Unitarized $ππ$ Scattering Chiral Amplitudes. https://doi.org/10.1088/0253-6102%2F36%2F5%2F563

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