The Banks - Zaks Expansion and “ Freezing ” in Perturbative QCD
نویسندگان
چکیده
The recent calculation of the four-loop β-function in QCD provides further evidence that the Banks-Zaks expansion in 16 1 2 −nf is sufficiently well behaved to be useful even for nf ≈ 2 light flavours. This expansion inherently predicts “freezing” of the QCD couplant at low energies as a perturbative effect. We consider the e+e− and Bjorken-sum-rule cases as examples.
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تاریخ انتشار 1997