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arXiv · 0808.0186

Circumstantial evidence for a soft nuclear symmetry energy at supra-saturation densities

Zhigang Xiao·Bao-An Li·Lie-Wen Chen·Gao-Chan Yong·Ming Zhang
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Abstract

Within an isospin- and momentum-dependent hadronic transport model it is shown that the recent FOPI data on the $π^-/π^+$ ratio in central heavy-ion collisions at SIS/GSI energies (Willy Reisdorf {\it et al.}, NPA {\bf 781}, 459 (2007)) provide circumstantial evidence suggesting a rather soft nuclear symmetry energy \esym at $ρ\geq 2ρ_0$ compared to the Akmal-Pandharipande-Ravenhall prediction. Some astrophysical implications and the need for further experimental confirmations are discussed.

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Zhigang Xiao, Bao-An Li, Lie-Wen Chen, Gao-Chan Yong, Ming Zhang. 2009-01-19. Circumstantial evidence for a soft nuclear symmetry energy at supra-saturation densities. https://doi.org/10.1103/physrevlett.102.062502

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