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alpha_s at low Q^2 from e+e- and tau data

Sven Menke
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Abstract

It has been shown in recent analyses by ALEPH [1] and OPAL [2] that precision QCD tests are possible with hadronic tau decays by comparing spectral moments of the hadronic decay ratio of the tau with QCD calculations. In principle e+e- data can be used in a similar manner by evaluating spectral moments of R. The current e+e- data is compared with the OPAL tau data and a prediction is made on the achievable accuracy of QCD tests with the projected precision of PEP-N [3].

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Sven Menke. 2001-06-02. alpha_s at low Q^2 from e+e- and tau data. https://arxiv.org/abs/hep-ex/0106011

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