Role of the axial U(1) anomaly in the chiral susceptibility of QCD at high temperature
Role of the axial U(1) anomaly in the chiral susceptibility of QCD at high temperature
复制标题
轴向 U(1) 异常在 QCD 高温手性敏感性中的作用
DOI：
10.1093/ptep/ptac001
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发表时间：
2022
影响因子：
3.5
通讯作者：
Suzuki K
中科院分区：
文献类型：
--
作者：
Aoki S;Aoki Y;Fukaya H;Hashimoto S;Rohrhofer C;Suzuki K
由于手征凝聚体是SU（2）L×SU（2）R对称破缺的序参量，手征磁化率或手征凝聚体对夸克质量的一阶导数常被用作QCD相变的探针。然而，手征凝聚体也破坏了轴U（1）对称性，这通常不被研究，因为它已经被异常破坏了，显然对跃迁的影响很小。我们研究了标量和赝标量通道中的双折射率，以量化轴向U（1）破缺对手性相变的贡献。利用手征对称格点Dirac算子及其本征模分解，我们将轴向U（1）破缺效应与其它效应分离开来.我们在双味QCD中的结果表明，在T = 190 MeV的温度下，在减去二次发散常数后，连通和非连通手征极化率都是由轴向U（1）破缺决定的.
The chiral susceptibility, or the first derivative of the chiral condensate with respect to the quark mass, is often used as a probe for the QCD phase transition since the chiral condensate is an order parameter ofSU(2)L×SU(2)Rsymmetry breaking. However, the chiral condensate also breaks the axialU(1) symmetry, which is usually not studied as it is already broken by the anomaly and apparently has little impact on the transition. We investigate the susceptibilities in the scalar and pseudoscalar channels in order to quantify how much the axialU(1) breaking contributes to the chiral phase transition. Employing a chirally symmetric lattice Dirac operator and its eigenmode decomposition, we separate the axialU(1) breaking effects from others. Our result in two-flavor QCD indicates that both of the connected and disconnected chiral susceptibilities are dominated by axialU(1) breaking at temperaturesT≳ 190 MeV after the quadratically divergent constant is subtracted.