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The pole structure of the unitary, crossing symmetric low energy $ππ$ scattering amplitudes

Z. Y. Zhou·G. Y. Qin·P. Zhang·Z. G. Xiao·H. Q. Zheng·N. Wu
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Abstract

The pole structure of the low energy $ππ$ scattering amplitudes is studied using a proper chiral unitarization method combined with crossing symmetry and the low energy phase shift data. It is found that the $σ$ pole position is at $M_σ=470\pm 50MeV$, $Γ_σ=570\pm 50MeV$. The existence of the virtual state pole in the IJ=20 channel is reconfirmed. Various threshold parameters are estimated and are found in general in good agreement with the results obtained from the Roy equation analyses.

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Z. Y. Zhou, G. Y. Qin, P. Zhang, Z. G. Xiao, H. Q. Zheng, N. Wu. 2005-02-20. The pole structure of the unitary, crossing symmetric low energy $ππ$ scattering amplitudes. https://doi.org/10.1088/1126-6708%2F2005%2F02%2F043

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