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arXiv · 0709.3239

Lambda-parameter of lattice QCD with Symanzik improved gluon actions

A. Skouroupathis·H. Panagopoulos
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Abstract

We compute the ratio Lambda_L/Lambda_MS, where the scale parameter Lambda_L is associated with a lattice formulation of QCD. We consider a 3-parameter family of gluon actions, which are most frequently used for O(a) improvement a` la Symanzik. The gluon action is put togeter with standard discretizations for fermions (Wilson/clover, overlap), to provide Lambda_L for several possible combinations of fermion and gluon actions. We employ the background field technique in order to calculate the 1PI 2-point function of the background field; this leads to the coupling constant renormalization function, Z_g, at 1-loop level. Our results are obtained for an extensive range of values for the Symanzik coefficients.

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BibTeXRIS

A. Skouroupathis, H. Panagopoulos. 2007-09-20. Lambda-parameter of lattice QCD with Symanzik improved gluon actions. https://doi.org/10.1103/physrevd.76.114514

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