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A Non-Perturbative Treatment of the Pion in the Linear Sigma-Model

Z. Aouissat·G. Chanfray·P. Schuck·J. Wambach
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Abstract

Using a non-perturbative method based on the selfconsistent Quasi-particle Random-Phase Approximation (QRPA) we describe the properties of the pion in the linear $σ$-model. It is found that the pion is massless in the chiral limit, both at zero- and finite temperature, in accordance with Goldstone's theorem.

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Z. Aouissat, G. Chanfray, P. Schuck, J. Wambach. 1996-04-16. A Non-Perturbative Treatment of the Pion in the Linear Sigma-Model. https://doi.org/10.1016/0375-9474(96)80011-f

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