Nonequilibrium chiral perturbation theory and disoriented chiral condensates

A. Gomez Nicola

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arXiv · hep-ph/9910533

Nonequilibrium chiral perturbation theory and disoriented chiral condensates

A. Gomez Nicola

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Abstract

We analyse the extension of Chiral Perturbation Theory to describe a meson gas out of thermal equilibrium. For that purpose, we let the pion decay constant be a time-dependent function and work within the Schwinger-Keldysh contour technique. A useful connection with curved space-time QFT allows to consistently renormalise the model, introducing two new low-energy constants in the chiral limit. We discuss the applicability of our approach within a Relativistic Heavy-Ion Collision environment. In particular, we investigate the formation of Disoriented Chiral Condensate domains in this model, via the parametric resonance mechanism.

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A. Gomez Nicola. 1999-10-28. Nonequilibrium chiral perturbation theory and disoriented chiral condensates. https://arxiv.org/abs/hep-ph/9910533

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