arXiv2018
A distinctive feature observed in lattice simulations of confining nonabelian gauge theories, such as Quantum Chromodynamics, is the presence of a dynamical mass for the gauge field in the low energy regime of the theory. In the Gribov-Zwanziger framework in the Landau gauge, such mass is a consequence of the generation of the dimension two condensates $\langle A_μ^aA_μ^a\rangle$ and $\langle \barφ_μ^{ab}φ_μ^{ab}-\barω_μ^{ab}ω_μ^{ab}\rangle$, where $A$ is the gluon field and the fields $\barφ$, $φ$, $\barω$, and $ω$ are Zwanziger's auxiliary fields. In this work, we show that, in the recently developed BRST-invariant version of the Refined Gribov-Zwanziger theory, these condensates can be introduced in a BRST-invariant way for a family of $R_ξ$ gauges. Their values are explicitly computed to first order and turn out to be independent of the gauge parameters contained in the gauge-fixing condition, as expected from the BRST invariance of the formulation. This fact supports the possibility of a gauge-parameter independent nonzero infrared gluon mass, whose value is the same as the one in the Landau gauge.