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arXiv · 1509.06737

Gauge fixing and the gluon propagator in renormalizable xi gauges

Pedro Bicudo·Daniele Binosi·Nuno Cardoso·Orlando Oliveira·Paulo J. Silva
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Abstract

Covariant $R_\xi$ gauge fixing is notoriously difficult for large lattice volumes, large $\xi$ and small $N_c$. We thoroughly test different convergence techniques, which allows the gauge fixing of lattice configurations with a total volume of (3.25 fm)$^4$, up to $\xi=0.5$. We are able to study the gluon propagator in the infrared region and its dependence on the gauge fixing parameter $\xi$. As expected, the longitudinal gluon dressing functions stay constant at their tree-level value $\xi$. Similar to the Landau gauge, the transverse $R_\xi$ gauge gluon propagators saturate at a non-vanishing value in the deep infrared for all values of $\xi$ studied. We compare with very recent continuum studies and perform a simple analysis of the found saturation with a dynamically generated effective gluon mass.

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Pedro Bicudo, Daniele Binosi, Nuno Cardoso, Orlando Oliveira, Paulo J. Silva. 2015-09-22. Gauge fixing and the gluon propagator in renormalizable xi gauges. https://arxiv.org/abs/1509.06737

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