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arXiv · 1305.0091

Energy dependence of pion in-medium effects on \pi^-/\pi^+ ratio in heavy-ion collisions

Jun Xu·Lie-Wen Chen·Che Ming Ko·Bao-An Li·Yu-Gang Ma
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Abstract

Within the framework of a thermal model with its parameters fitted to the results from an isospin-dependent Boltzmann-Uehling-Uhlenbeck (IBUU) transport model, we study the pion in-medium effect on the charged-pion ratio in heavy-ion collisions at various energies. We find that due to the cancellation between the effects from pion-nucleon s-wave and p-wave interactions in nuclear medium, the \pi^-/\pi^+ ratio generally decreases after including the pion in-medium effect. The effect is larger at lower collision energies as a result of narrower pion spectral functions at lower temperatures.

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Jun Xu, Lie-Wen Chen, Che Ming Ko, Bao-An Li, Yu-Gang Ma. 2013-05-01. Energy dependence of pion in-medium effects on \pi^-/\pi^+ ratio in heavy-ion collisions. https://doi.org/10.1103/physrevc.87.067601

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