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arXiv · 0710.0583

The SF running coupling with four flavours of staggered quarks

P. Perez-Rubio·S. Sint
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Abstract

In order to study the running coupling in four-flavour QCD, we review the set-up of the Schrödinger functional (SF) with staggered quarks. Staggered quarks require lattices which, in the usual counting, have even spatial lattice extent $L/a$ while the time extent $T/a$ must be odd. Setting $T=L$ is therefore only possible up to ${\rm O}(a)$, which introduces different cutoff effects already in the pure gauge theory. We re-define the SF such as to cope with this situation and determine the corresponding classical background field. A perturbative calculation yields the coefficient of the pure gauge ${\rm O}(a)$ boundary counterterm to one-loop order.

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P. Perez-Rubio, S. Sint. 2007-10-03. The SF running coupling with four flavours of staggered quarks. https://arxiv.org/abs/0710.0583

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