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arXiv · 1908.09118

Chiral perturbation theory vs. Linear Sigma Model in a chiral imbalance medium

A. A. Andrianov·V. A. Andrianov·D. Espriu
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Abstract

We compare Chiral Perturbation Theory (ChPT) and the Linear Sigma Model (LSM) as realizations of low energy QCD for light mesons in a chirally imbalanced medium. The relations between the low-energy constants of the Chiral Lagrangian and the corresponding constants of the Linear Sigma Model are established as well as the expressions for the decay constant of the $π$-meson in the medium and the mass of the $a_0$. In the large $N_c$ count taken from QCD the correspondence of ChPT and LSM is remarkably good and give a solid ground for search of chiral imbalance manifestation in pion physics. A possible experimental detection of chiral imbalance tracks (and therefore a phase with Local Parity Breaking) in the charged pion decays inside the fireball is outlined.

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A. A. Andrianov, V. A. Andrianov, D. Espriu. 2020-05-17. Chiral perturbation theory vs. Linear Sigma Model in a chiral imbalance medium. https://arxiv.org/abs/1908.09118

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