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How to See the Chiral Structure of QCD Vacuum in Low Energy $π-π$ Scattering

Jan Stern
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Abstract

Precise measurement of the $ππ$-phase shift $δ^0_0(E)$ at very low energies would provide, for the first time, the experimental evidence in favour of or against the existence of a large quark condensate in the QCD vacuum, which is standardly postulated as the mechanism of the spontaneous breakdown of chiral symmetry in QCD. The contribution of Da$ϕ$ne to this discovery could be decisive.

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Jan Stern. 1995-10-17. How to See the Chiral Structure of QCD Vacuum in Low Energy $π-π$ Scattering. https://arxiv.org/abs/hep-ph/9510318

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