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First results on the running coupling in QCD with two massless flavours

Achim Bode·Roberto Frezzotti·Bernd Gehrmann·Martin Hasenbusch·Jochen Heitger·Karl Jansen·Stefan Kurth·Juri Rolf·Hubert Simma·Stefan Sint·Rainer Sommer·Peter Weisz·Hartmut Wittig·Ulli Wolff
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Abstract

We report on the non-perturbative computation of the running coupling of two-flavour QCD in the Schr"odinger functional scheme. The corresponding Lambda-parameter, which describes the coupling strength at high energy, is related to a low energy scale which still remains to be connected to a hadronic ``experimentally'' observable quantity. We find the non-perturbative evolution of the coupling indispensable to avoid untolerable errors in the estimated Lambda-parameter.

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Achim Bode, Roberto Frezzotti, Bernd Gehrmann, Martin Hasenbusch, Jochen Heitger, Karl Jansen, Stefan Kurth, Juri Rolf, Hubert Simma, Stefan Sint, Rainer Sommer, Peter Weisz, Hartmut Wittig, Ulli Wolff. 2001-05-28. First results on the running coupling in QCD with two massless flavours. https://doi.org/10.1016/s0370-2693(01)00857-7

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