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arXiv 0908.0737hep-th
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重离子碰撞中的退禁闭、单极和新现象

Deconfinement, Monopoles and New Phenomena in Heavy Ion Collisions

Edward Shuryak

摘要:

我们讨论了被视为两种等离子体、电(夸克和胶子)以及磁荷准粒子混合物的夸克-胶子等离子体的“磁情景”的各种表现。在去禁闭相变附近,$T\approx T_c$非常小的自由夸克密度应该导致电场的屏蔽可以忽略不计,而磁屏蔽仍然很强。这样的结果应该是QGP的“日冕”的存在,以类似于太阳的方式,其中电场影响扰动的传播,甚至形成亚稳态通量管。描述它的自然工具是(双重)磁流体力学:在可观察到的结果中,声音分裂成两种模式,具有较大和较小的速度。后者可以为零,暗示压力稳定的通量管的形成。值得注意的是,RHIC最近的实验发现显示了类似于“日冕结构”的预期效应。在具有大- $p_t$触发的双强子关联函数中,存在一个“锥”和一个“硬脊”,而所谓的“软脊”是在没有硬触发时所看到的类似结构。它们似乎是通量管的残余物,与天真的预期相反,通量管在近$T_c$物质中似乎比在真空中的束缚弦更不容易断裂。

英文摘要:

We discuss various manifestations of the "magnetic scenario" for the quark-gluon plasma viewed as a mixture of two plasmas, of electrically (quark and gluons) as well as magnetically charged quasiparticles. Near the deconfinement phase transition, $T\approx T_c$ very small density of free quarks should lead to negligible screening of electric field while magnetic screening remains strong. The consequence of this should be existence of a "corona" of the QGP, in a way similar to that of the Sun, in which electric fields influence propagation of perturbations and even form metastable flux tubes. The natural tool for its description is (dual) magnetohydrodynamics: among observable consequences is splitting of sound into two modes, with larger and smaller velocity. The latter can be zero, hinting for formation of pressure-stabilized flux tubes. Remarkably, recent experimental discoveries at RHIC show effects similar to expected for "corona structures". In dihadron correlation function with large-$p_t$ trigger there are a "cone" and a "hard ridge",while the so called "soft ridge" is a similar structure seen without hard trigger. They seem to be remnants of flux tubes, which -- contrary to naive expectations -- seem to break less often in near-$T_c$ matter than do confining strings in vacuum.

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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