论文标题
红外QCD中的小参数：触发衰减常数
Small parameters in infrared QCD: The pion decay constant
论文作者
论文摘要
我们继续根据curci ferrari有效的lagrangian进行对QCD动力学的研究，这是faddeev-popov的变形，其中具有树级Gluon质量术语的Landau仪表中。在先前的工作中，我们研究了在夸克传播器的水平上，尤其是组成夸克质量的动态生成的手性对称性破裂的动力学。在本文中，我们研究了相关的金石模式，斜杆，并计算手性极限中的斜腐衰变常数。我们的方法利用了这样一个事实，即纯量规部门中的耦合（在泰勒方案中定义）是扰动的，如晶格模拟中所观察到的那样，在QCD的低能状态下，该晶格模拟与$ 1/n_c $ - expansion一起允许在QCD低能方面具有系统的，可控制的近似值。在领先的秩序中，这导致了众所周知的彩虹潮流。我们研究模型的参数空间区域，该区域给出了茶衰减常数的物理值。这允许人们使用物理测量的数量来约束Gluon质量参数作为耦合的函数。
We continue our investigation of the QCD dynamics in terms of the Curci-Ferrari effective Lagrangian, a deformation of the Faddeev-Popov one in the Landau gauge with a tree-level gluon mass term. In a previous work we have studied the dynamics of chiral symmetry breaking at the level of the quark propagator and, in particular, the dynamical generation of a constituent quark mass. In the present article, we study the associated Goldstone mode, the pion, and we compute the pion decay constant in the chiral limit. Our approach exploits the fact that the coupling (defined in the Taylor scheme) in the pure gauge sector is perturbative, as observed in lattice simulations which, together with a $1/N_c$-expansion, allows for a systematic, controllable approximation scheme in the low energy regime of QCD. At leading order, this leads to the well-known rainbow-ladder resummation. We study the region of parameter space of the model that gives physical values of the pion decay constant. This allows one to constrain the gluon mass parameter as a function of the coupling using a physically measured quantity.
