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arXiv · hep-ph/0203170

Sigma-meson in hot and dense matter

M. K. Volkov·A. E. Radzhabov·N. L. Russakovich
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Abstract

An important role of the scalar isoscalar sigma-meson in the low-energy physics is discussed. The behavior of the sigma-meson in the hot and dense medium is studied. It is shown that in the vicinity of critical values of temperature(T) and chemical potential(m) the sigma-meson can become a sharp resonance. This effect can lead to a strong enhancement of the processes pi pi -> gamma gamma and pi pi-> pi pi near the two-pion threshold. Experimental observation of this phenomenon can be interpreted as a signal of approaching the domain where the chiral symmetry restoration and phase transition of the hadron matter into quark-gluon plasma take place.

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M. K. Volkov, A. E. Radzhabov, N. L. Russakovich. 2002-03-22. Sigma-meson in hot and dense matter. https://doi.org/10.1134/1.1577922

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