αs at Low Q 2 from e + e − and τ Data
نویسنده
چکیده
It has been shown in recent analyses by ALEPH [1] and OPAL [2] that precision QCD tests are possible with hadronic τ decays by comparing spectral moments of the hadronic decay ratio of the τ 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 τ 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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