Systematic parameter study of hadron spectra and elliptic flow from viscous hydrodynamic simulations of Au+Au collisions at s NN =200 GeV
Systematic parameter study of hadron spectra and elliptic flow from viscous hydrodynamic simulations of Au+Au collisions at s NN =200 GeV
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DOI：
10.1103/physrevc.82.054904
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发表时间：
2010-10
影响因子：
3.1
通讯作者：
C. Shen;U. Heinz;P. Huovinen;Huichao Song
中科院分区：
文献类型：
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作者：
C. Shen;U. Heinz;P. Huovinen;Huichao Song
利用（$2+1$）维粘性流体动力学程序vish 2 $+$1 [H. Song和U.海因茨，物理学快报。B 658，279（2008）; H. Song和U.海因茨，物理学评论C 77，064901（2008）; H.宋博士论文，俄亥俄州州立大学，2009年]，我们提出了系统的研究依赖的π介子和质子的横动量谱和椭圆流在$200 A $ GeV的Au$+$Au碰撞的流体动力学模型的参数（热化时间，初始熵密度分布，去耦温度，状态方程，比剪切粘度$\ensuremath{\eta}/s$）。我们确定质子谱的斜率之间的张力，这（在流体动力学模拟，假设一个恒定的剪切粘度熵密度比）更喜欢较大的$\ensuremath{\eta}/s$值，和斜率的${p}_{T}$依赖的带电强子椭圆流，这更喜欢较小的$\ensuremath{\eta}/s$值。改变其他模型参数似乎并不允许这种张力的溶解。
Using the ($2+1$)-dimensional viscous hydrodynamic code vish2$+$1 [H. Song and U. Heinz, Phys. Lett. B 658, 279 (2008); H. Song and U. Heinz, Phys. Rev. C 77, 064901 (2008); H. Song, Ph. D. thesis, The Ohio State University, 2009], we present systematic studies of the dependence of pion and proton transverse-momentum spectra and their elliptic flow in $200A$ GeV Au$+$Au collisions on the parameters of the hydrodynamic model (thermalization time, initial entropy density distribution, decoupling temperature, equation of state, and specific shear viscosity $\ensuremath{\eta}/s$). We identify a tension between the slope of the proton spectra, which (within hydrodynamic simulations that assume a constant shear viscosity to entropy density ratio) prefer larger $\ensuremath{\eta}/s$ values, and the slope of the ${p}_{T}$ dependence of charged hadron elliptic flow, which prefers smaller values of $\ensuremath{\eta}/s$. Changing other model parameters does not appear to permit dissolution of this tension.