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arXiv · 0802.0862

O(a) improvement of the HYP static axial and vector currents at one-loop order of perturbation theory

A. Grimbach·D. Guazzini·F. Knechtli·F. Palombi
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Abstract

We calculate analytically the improvement coefficients of the static axial and vector currents in O(a) improved lattice QCD at one-loop order of perturbation theory. The static quark is described by the hypercubic action, previously introduced in the literature in order to improve the signal-to-noise ratio of static observables. Within a Schroedinger Functional setup, we derive the Feynman rules of the hypercubic link in time-momentum representation. The improvement coefficients are obtained from on-shell correlators of the static axial and vector currents. As a by-product, we localise the minimum of the static self-energy as a function of the smearing parameters of the action at one-loop order and show that the perturbative minimum is close to its non-perturbative counterpart.

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A. Grimbach, D. Guazzini, F. Knechtli, F. Palombi. 2008-02-06. O(a) improvement of the HYP static axial and vector currents at one-loop order of perturbation theory. https://doi.org/10.1088/1126-6708%2F2008%2F03%2F039

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