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arXiv · hep-lat/9809130

An Estimate of alpha_S from Bottomonium in Unquenched QCD

SESAM Collaboration·A. Spitz·N. Eicker·S. Guesken·H. Hoeber·P. Lacock·T. Lippert·K. Schilling·T. Struckmann·P. Ueberholz·J. Viehoff
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Abstract

We estimate the strong coupling constant from the perturbative expansion of the plaquette. The scale is set by the 2S-1S and 1P-1S splittings in bottomonium which are computed in NRQCD on dynamical gauge configurations with nf=2 degenerate Wilson quarks at intermediate masses. We have increased the statistics of our spectrum calculation in order to reliably extrapolate in the sea-quark mass. We find a value of alpha_MS(m_Z) = 0.1118(26) which is somewhat lower than previous estimates within NRQCD.

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SESAM Collaboration, A. Spitz, N. Eicker, S. Guesken, H. Hoeber, P. Lacock, T. Lippert, K. Schilling, T. Struckmann, P. Ueberholz, J. Viehoff. 1998-09-16. An Estimate of alpha_S from Bottomonium in Unquenched QCD. https://doi.org/10.1016/s0920-5632(99)85062-2

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