Excess of pions with chiral symmetry restoration
نویسندگان
چکیده
We study the effect of the chiral phase transition on pion production in hot hadronic matter. The phase of restored chiral symmetry is characterized by the appearance of the scalar σ-meson as a chiral partner of the pion as well as by the degeneracy of the vector and axial-vector mesons. We find rapid thermal and chemical equilibration of these degrees of freedom in the symmetric phase. Provided that the chiral transition temperature is not considerably high, the presence of a chirally symmetric phase will result in ∼ 1.6 times more thermal pions in the final state. Typeset using REVTEX 1
منابع مشابه
O ct 1 99 4 SUNY - NTG - 94 - 54 October 1994 WHERE THE NUCLEAR PIONS ARE
Three recent experiments, which looked at pionic effects in nuclei have concluded that there are no excess pions. This puts into serious question the conventional meson-exchange picture of the nucleon-nucleon interaction. Based on arguments of partial restoration of chiral symmetry with density we propose a resolution to this problem.
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