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arXiv 1208.2537hep-phnucl-th
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从手征磁波到椭圆流的电荷依赖性

From the chiral magnetic wave to the charge dependence of elliptic flow

Y. Burnier, D. E. Kharzeev, J. Liao, H. -U. Yee

摘要:

在重离子碰撞中形成的夸克胶子等离子体中含有在外磁场中演化的带电手征费米子。在有限密度的电荷或重子数(由核阻止或涨落引起)下,三角形反常在等离子体中感应出手征磁波(CMW)。CMW首先诱导左右手征电荷沿磁场分离;由此产生的偶极轴向电荷密度反过来诱导方向相反的矢量电荷电流,导致夸克-胶子等离子体的电四极矩。在强集体流的推动下,电四极矩转化为椭圆流系数的电荷依赖性,使得$v_2(π^+) < v_2(π^-)$(在正净电荷处)。利用最新的产生磁场的定量模拟和求解CMW方程,我们进一步定量估计产生的$v_2$分裂及其中心依赖性。我们比较的结果与现有的实验数据。

英文摘要:

The quark-gluon plasma formed in heavy ion collisions contains charged chiral fermions evolving in an external magnetic field. At finite density of electric charge or baryon number (resulting either from nuclear stopping or from fluctuations), the triangle anomaly induces in the plasma the Chiral Magnetic Wave (CMW). The CMW first induces a separation of the right and left chiral charges along the magnetic field; the resulting dipolar axial charge density in turn induces the oppositely directed vector charge currents leading to an electric quadrupole moment of the quark-gluon plasma. Boosted by the strong collective flow, the electric quadrupole moment translates into the charge dependence of the elliptic flow coefficients, so that $v_2(π^+) < v_2(π^-)$ (at positive net charge). Using the latest quantitative simulations of the produced magnetic field and solving the CMW equation, we make further quantitative estimates of the produced $v_2$ splitting and its centrality dependence. We compare the results with the available experimental data.

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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