论文标题
手性有效的$ u（1）_ {\ rm a} $对称修复
Chiral and effective $U(1)_{\rm A}$ symmetry restoration in QCD
论文作者
论文摘要
接近手性极限的QCD相跃迁的性质和位置限制了QCD的相结构，而物理脉冲质量在非变化密度下。在小型pion质量中，明确的$ u（1）_ {\ rm a} $ - 由非平凡拓扑密度引起的破裂至关重要。它触发了't Hooft的相互作用，并且在低动量尺度下的四夸克相互作用的相互作用中也表现出来。在目前的工作中，我们对有限温度下的QCD动力学的四夸克相互作用的出现进行了FIFEZ完整的分析，但在大动量尺度下以给定的“ T Hooft耦合”。后者的变化使我们能够测试发现的鲁棒性。考虑到't Hooft耦合的拓扑运行的效果，我们的分析表明，QCD的手性转变具有两个无数夸克的口味，属于$ O（4）$通用类。
The nature and location of the QCD phase transition close to the chiral limit restricts the phase structure of QCD with physical pion masses at non-vanishing density. At small pion masses, explicit $U(1)_{\rm A}$-breaking, as induced by a non-trivial topological density, is of eminent importance. It triggers the 't Hooft interactions and also manifests itself in the interplay of four-quark interactions at low momentum scales. In the present work, we perform a Fierz-complete analysis of the emergence of four-quark interactions from the QCD dynamics at finite temperature, subject to a given 't Hooft coupling at large momentum scales. The variation of the latter allows us to test the robustness of our findings. Taking an estimate of the effect of the topological running of the 't Hooft coupling into account, our analysis suggests that the chiral transition in QCD with two massless quark flavours falls into the $O(4)$ universality class.
