Asymptotic structure of perturbative series for τ lepton observables
نویسندگان
چکیده
We analyze τ lepton decay observables, namely moments of the hadronic spectral density in the finite energy interval (0, Mτ ), within finite order perturbation theory including α s corrections. The start of the asymptotic growth of the perturbation theory series is found at this order in a scheme invariant manner. We establish the ultimate accuracy of finite order perturbation theory predictions and discuss the construction of optimal observables.
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تاریخ انتشار 1999