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arXiv · hep-ph/9703208

New high order relations between physical observables in perturbative QCD

S. Groote·J. G. Körner·A. A. Pivovarov·K. Schilcher
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Abstract

We exploit the fact that within massless perturbative QCD the same Green's function determines the hadronic contribution to the $τ$ decay width and the moments of the $e^+e^-$ cross section. This allows one to obtain relations between physical observables in the two processes up to an unprecedented high order of perturbative QCD. A precision measurement of the $τ$ decay width allows one then to predict the first few moments of the spectral density in $e^+e^-$ annihilations integrated up to $s\sim m_τ^2$ with high accuracy. The proposed tests are in reach of present experimental capabilities.

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S. Groote, J. G. Körner, A. A. Pivovarov, K. Schilcher. 1997-03-01. New high order relations between physical observables in perturbative QCD. https://doi.org/10.1103/physrevlett.79.2763

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