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Single and double pi^{-}/pi^{+} ratios in heavy-ion reactions as probes of the high-density behavior of the nuclear symmetry energy

Gao-Chan Yong·Bao-An Li·Lie-Wen Chen·Wei Zuo
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Abstract

Based on an isospin- and momentum-dependent hadronic transport model IBUU04, effects of the nuclear symmetry energy on the single and double pi^{-}/pi^{+}ratios in central reactions of ^{132}Sn+^{124}Sn and ^{112}Sn+^{112}Sn at a beam energy of 400 MeV/nucleon are studied. It is found that around the Coulomb peak of the single pi^{-}/pi^{+} ratio the double pi^{-}/pi^{+} ratio taken from the two isotopic reactions retains about the same sensitivity to the density dependence of nuclear symmetry energy. Because the double pi^{-}/pi^{+}ratio can reduce significantly the systematic errors, it is thus a more effective probe for the high-density behavior of the nuclear symmetry energy.

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Gao-Chan Yong, Bao-An Li, Lie-Wen Chen, Wei Zuo. 2006-03-02. Single and double pi^{-}/pi^{+} ratios in heavy-ion reactions as probes of the high-density behavior of the nuclear symmetry energy. https://doi.org/10.1103/physrevc.73.034603

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