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arXiv · hep-ph/9611267

Perturbative QCD and Tau Decay

Eric Braaten
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Abstract

Sufficiently inclusive observables in the decay of the tau lepton can be calculated using the methods of perturbative QCD. These include the asymmetry parameter $A_τ$ that determines that angular distribution of the total hadron momentum in the decay of a polarized tau. It should be possible to measure $A_τ$ accurately using existing data from LEP. Reliable estimates of theoretical errors are essential in order to determine whether a given observable is sufficiently inclusive to be calculated using perturbative methods. The theoretical uncertainties due to higher orders in $α_s$ can be estimated using recent calculations to all orders in the large-$(33-2N_f)$ limit. These estimates indicate that tau decay data can be used to determine $α_s(M_Z)$ to a precision of 2% or better.

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Eric Braaten. 1996-11-07. Perturbative QCD and Tau Decay. https://doi.org/10.1016/s0920-5632(97)00233-8

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