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Non-renormalization of the full correlator at two-loop order

F. Jegerlehner·O. V. Tarasov
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Abstract

By explicit calculation of the two-loop QCD corrections we show that for singlet axial and vector currents the full off-shell correlation function in the limit of massless fermions is proportional to the one-loop result, when calculated in the MS-bar scheme. By the same finite renormalization which is needed to make the one-loop anomaly exact to all orders, we arrive at the conclusion that two-loop corrections are absent altogether, for the complete correlator not only its anomalous part. In accordance with the one-loop nature of the correlator, one possible amplitude, which seems to be missing by accident at the one-loop level, also does not show up at the two-loop level.

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F. Jegerlehner, O. V. Tarasov. 2006-04-06. Non-renormalization of the full correlator at two-loop order. https://doi.org/10.1016/j.nuclphysbps.2006.03.016

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