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arXiv · 1311.1934

Discretization Errors for the Gluon and Ghost Propagators in Landau Gauge using NSPT

Jakob Simeth·Andre Sternbeck·Ernst-Michael Ilgenfritz·Holger Perlt·Arwed Schiller
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Abstract

The subtraction of hypercubic lattice corrections, calculated at 1-loop order in lattice perturbation theory (LPT), is common practice, e.g., for determinations of renormalization constants in lattice hadron physics. Providing such corrections beyond 1-loop order is however very demanding in LPT, and numerical stochastic perturbation theory (NSPT) might be the better candidate for this. Here we report on a first feasibility check of this method and provide (in a parametrization valid for arbitrary lattice couplings) the lattice corrections up to 3-loop order for the SU(3) gluon and ghost propagators in Landau gauge. These propagators are ideal candidates for such a check, as they are available from lattice simulations to high precision and can be combined to a renormalization group invariant product (Minimal MOM coupling) for which a 1-loop LPT correction was found to be insufficient to remove the bulk of the hypercubic lattice artifacts from the data. As a bonus, we also compare our results with the ever popular H(4) method.

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Jakob Simeth, Andre Sternbeck, Ernst-Michael Ilgenfritz, Holger Perlt, Arwed Schiller. 2013-11-08. Discretization Errors for the Gluon and Ghost Propagators in Landau Gauge using NSPT. https://arxiv.org/abs/1311.1934

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