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arXiv 0906.2808hep-ph
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热QCD中拓扑诱导的局部P和CP破坏

Topologically induced local P and CP violation in hot QCD

D. E. Kharzeev

摘要:

在强相互作用中,P和CP破坏的量存在非常严格的实验界限。然而,非阿贝尔拓扑解的存在和轴反常使得QCD中的CP不变性问题变得非平凡(“强CP问题”)。即使在不存在整体P和CP破坏的情况下,QCD真空中拓扑荷的涨落在手征对称性破缺以及强子的质谱和其它性质中也将起重要作用。在这里,我认为,在热QCD物质的拓扑涨落可以成为直接观察到的存在下,一个非常强烈的外部磁场诱导本地P-和CP-奇效应。这些局部宇称违反现象可以用麦克斯韦-陈-西蒙斯(Maxwell-Chern-Simons)或轴子电动力学作为有效理论来描述。热QCD物质中的局域P和CP破坏可以通过“手征磁效应”--相对论离子碰撞产生的电荷沿磁场轴的分离--在实验中观察到。最近在RHIC的STAR合作组中发现了相对于重离子碰撞反应面电荷分离的证据。

英文摘要:

Very stringent experimental bounds exist on the amount of P and CP violation in strong interactions. Nevertheless, the presence of non-Abelian topological solutions and the axial anomaly make the issue of CP invariance in QCD non-trivial ("the strong CP problem"). Even in the absence of a global P and CP violation the fluctuations of topological charge in the QCD vacuum are expected to play an important role in the breaking of chiral symmetry, and in the mass spectrum and other properties of hadrons. Here I argue that topological fluctuations in hot QCD matter can become directly observable in the presence of a very intense external magnetic field by inducing local P- and CP- odd effects. These local parity-violating phenomena can be described by using the Maxwell-Chern-Simons, or axion, electrodynamics as an effective theory. Local P and CP violation in hot QCD matter can be observed in experiment through the "chiral magnetic effect" - the separation of electric charge along the axis of magnetic field that is created by the colliding relativistic ions. There is a recent evidence for the electric charge separation relative to the reaction plane of heavy ion collisions from the STAR Collaboration at RHIC.

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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