Existence of Sigma Meson in Pi-pi Scattering *
نویسنده
چکیده
In this talk I summarize a recently proposed mechanism to understand ππ scattering to 1 GeV. The model is motivated by the 1/NC expansion to QCD, and includes a current algebra contact term and resonant pole exchanges. Chiral symmetry plays an important role in restricting the form of the interactions. The existence of a broad low energy scalar (σ) is indicated.
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