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arXiv 1406.5322hep-phnucl-th
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有限夸克化学势下重夸克在$T_c$周围的输运系数

Transport coefficients of heavy quarks around $T_c$ at finite quark chemical potential

H. Berrehrah, P. B. Gossiaux, J. Aichelin, W. Cassing, J. M. Torres-Rincon, E. Bratkovskaya

摘要:

在动力学准粒子模型(DQPM)中,用输运系数研究了有限温度下重夸克与部分子环境的相互作用.在动力学准粒子模型(DQPM)中,采用$T$和有限夸克化学势$μ_q$,模拟了热力学平衡下的格子QCD结果(包括部分子状态方程).这些结果与接近临界温度$T_c$的核多体计算结果是对立的。强子和部分子的空间扩散系数顺利加入,并显示出一个明显的最小值周围的$T_c$,在$μ_q=0$以及在有限的$μ_q$。接近并高于$T_c$,其绝对值与$μ_q=0$的IQCD计算相匹配。重夸克输运系数从强子到部分子介质的平滑过渡对应于与晶格计算一致的交叉,并且与微扰QCD(pQCD)计算有很大的不同,后者在$T_c$处显示出很大的不连续性。这表明在$T_c$附近,动态修饰的有质量部分子而不是无质量pQCD部分子是夸克-胶子等离子体中的有效自由度。

英文摘要:

The interactions of heavy quarks with the partonic environment at finite temperature $T$ and finite quark chemical potential $μ_q$ are investigated in terms of transport coefficients within the Dynamical Quasi-Particle model (DQPM) designed to reproduce the lattice-QCD results (including the partonic equation of state) in thermodynamic equilibrium. These results are confronted with those of nuclear many-body calculations close to the critical temperature $T_c$. The hadronic and partonic spatial diffusion coefficients join smoothly and show a pronounced minimum around $T_c$, at $μ_q=0$ as well as at finite $μ_q$. Close and above $T_c$ its absolute value matches the lQCD calculations for $μ_q=0$. The smooth transition of the heavy quark transport coefficients from the hadronic to the partonic medium corresponds to a cross over in line with lattice calculations, and differs substantially from perturbative QCD (pQCD) calculations which show a large discontinuity at $T_c$. This indicates that in the vicinity of $T_c$ dynamically dressed massive partons and not massless pQCD partons are the effective degrees-of-freedom in the quark-gluon plasma.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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