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arXiv · hep-lat/9311054

Alpha_s from the Lattice Potential

K. Schilling·G. S. Bali
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Abstract

We present an extensive study on the direct determination of the running coupling alpha_s from the static quark antiquark force at short distances, in quenched QCD. We find from our high statistics potential analysis that alpha_qq exhibits two-loop asymptotic behaviour for momenta as low as .5 GeV. As a result, we determine the zero flavour Lambda-parameter to be Lambda^0_MSBAR = 0.630(38)\sqrtσ = 293(18)^{+25}_{-63} MeV. A rough estimate of full QCD effects leads to the five flavour value alpha_MSBAR(m_Z) = .102^{+6}_{-11}. A comparison with other lattice results is made.

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K. Schilling, G. S. Bali. 1993-11-29. Alpha_s from the Lattice Potential. https://doi.org/10.1016/0920-5632(94)90331-x

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