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arXiv · 0812.2484

The determination of alpha_s(M_z) from perturbative analyses of short-distance-sensitive lattice QCD observables revisited

K. Maltman·D. Leinweber·P. Moran·A. Sternbeck
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Abstract

The determination of alpha_s(M_Z) via perturbative analyses of short-distance-sensitive lattice observables is revisited, incorporating new lattice data and performing a modified version of the original analysis. The analysis employs two high-intrinsic-scale observables, log (W_11) and log(W_12), and one lower-intrinsic-scale observable, log(W_12/u_0^6). We find good consistency among the values extracted using the different observables and a final result, alpha_s(M_Z)=0.1192(11), in excellent agreement with various recent non-lattice determinations, as well as with the results of a similar, but not identical, re-analysis by the HPQCD collaboration. The relation between the two re-analyses is discussed, focussing on the complementarity of the two approaches.

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K. Maltman, D. Leinweber, P. Moran, A. Sternbeck. 2008-12-12. The determination of alpha_s(M_z) from perturbative analyses of short-distance-sensitive lattice QCD observables revisited. https://arxiv.org/abs/0812.2484

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