Global parameterization of $$\pi \pi $$ scattering up to 2 $${\mathrm {\,GeV}}$$

Pi Pi scattering in an effective chiral

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.

Pi-pi Scattering Lengths in the Light of Precision Measurements

Existence of Sigma Meson in Pi-pi Scattering *

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.

pi - pi scattering in a QCD-based model field theory.

A model field theory, in which the interaction between quarks is mediated by dressed vector boson exchange, is used to analyse the pionic sector of QCD. It is shown that this model, which incorporates dynamical chiral symmetry breaking, asymptotic freedom and quark confinement, allows one to calculate fπ, mπ, rπ and the partial wave amplitudes in π-π scattering and obtain good agreement with th...

Observation of eta' decays to pi+pi-pi0 and pi+pi-e+e-.

Using psi(2S)-->pi;{+}pi;{-}J/psi, J/psi-->gammaeta;{'} events acquired with the CLEO-c detector at the CESR e;{+}e;{-} collider, we make the first observations of the decays eta;{'}-->pi;{+}pi;{-}pi;{0} and eta;{'}-->pi;{+}pi;{-}e;{+}e;{-}, measuring absolute branching fractions (37_{-9};{+11}+/-4)x10;{-4} and (25_{-9};{+12}+/-5)x10;{-4}, respectively. For eta;{'}-->pi;{+}pi;{-}pi;{0}, this re...