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arXiv · 0810.2933

Study of moments of event shapes and a determination of \as using \epem annihilation data from \Jade

Christoph Pahl·Siegfried Bethke·Stefan Kluth·Jochen Schieck
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Abstract

Data from \epem annihilation into hadrons, collected by the \Jade experiment at centre-of-mass energies between 14 GeV and 44 GeV, are used to study moments of event shape distributions. Models with hadronisation parameters tuned to the LEP 1 precision data provide an adequate description of the low energy data studied here. The NLO QCD calculations, however, show systematic deficiencies for some of the moments. The strong coupling measured from the moments which are reasonably described by NLO QCD, \asmz=0.1287\pm0.0007\stat\pm0.0011\expt\pm0.0022\had\pm0.0075\theo is consistent with the world average.

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Christoph Pahl, Siegfried Bethke, Stefan Kluth, Jochen Schieck. 2008-10-16. Study of moments of event shapes and a determination of \as using \epem annihilation data from \Jade. https://doi.org/10.1140/epjc/s10052-009-0930-5 10.1140/epjc/s10052-009-1032-0

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