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Pi Pi Scattering and Scalar Mesons in an Effective Chiral Lagrangian

Masayasu Harada
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Abstract

In this talk I summarize recently proposed mechanisms to understand pi pi scattering to 1 GeV in an effective chiral Lagrangian. The Lagrangian includes higher resonances in addition to pions consistently with the chiral symmetry. Iso-spin zero S-wave partial wave amplitude is reproduced up till about 1.2 GeV by including a pion self-interaction and resonant pole exchanges of rho, f0(980) and sigma derived from the effective chiral Lagrangian. The best fit shows that sigma has a mass of around 560 MeV and a width of about 370 MeV.

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Masayasu Harada. 2000-09-05. Pi Pi Scattering and Scalar Mesons in an Effective Chiral Lagrangian. https://arxiv.org/abs/hep-ph/0009051

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