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arXiv · 1104.2698

Decay of a scalar $\sigma$-meson near the critical end-point in the PNJL model

A. V. Friesen·Yu. L. Kalinovsky·V. D. Toneev
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Abstract

Properties of a scalar $\sigma$-meson are investigated in the two-flavor Nambu-Jona-Lasinio model with the Polyakov loop. Model analysis of the phase diagram of strong interacting matter is performed. The temperature dependence of the $\sigma\rightarrow\pi\pi$ decay width is studied at the zero chemical potential and near the critical end-point. The calculated strong coupling constant $g_{\sigma\pi\pi}$ and the decay width are compared with available experimental data and other model results. Nonthermal enhancement of the total decay width is noted for the $\sigma$ meson near the critical end-point when the condition $m_\sigma\geq2m_\pi$ is broken.

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A. V. Friesen, Yu. L. Kalinovsky, V. D. Toneev. 2011-04-14. Decay of a scalar $\sigma$-meson near the critical end-point in the PNJL model. https://doi.org/10.1134/s1547477112010104

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