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Near-threshold pion production with radioactive beams at the Rare Isotope Accelerator

Bao-An Li·Gao-Chan Yong·Wei Zuo
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Abstract

Using an isospin- and momentum-dependent transport model we study near-threshold pion production in heavy-ion collisions induced by radioactive beams at the planned Rare Isotope Accelerator (RIA). We revisit the question of probing the high density behavior of nuclear symmetry energy $E_{sym}(ρ)$ using the $π^-/π^+$ ratio. It is found that both the total and differential $π^-/π^+$ ratios remain sensitive to the $E_{sym}(ρ)$ when the momentum-dependence of both the isoscalar and isovector potentials are consistently taken into account. Moreover, the multiplicity and spectrum of $π^-$ mesons are found more sensitive to the $E_{sym}(ρ)$ than those of $π^+$ mesons. Finally, effects of the Coulomb potential on the pion spectra and $π^-/π^+$ ratio are also discussed.

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Bao-An Li, Gao-Chan Yong, Wei Zuo. 2004-11-11. Near-threshold pion production with radioactive beams at the Rare Isotope Accelerator. https://doi.org/10.1103/physrevc.71.014608

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