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arXiv · 1106.5520

The four-dimensional helicity scheme and dimensional reconstruction

Radja Boughezal·Kirill Melnikov·Frank Petriello
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Abstract

The four-dimensional helicity regularization scheme is often used in one-loop QCD computations. It was recently argued in Ref. [1] that this scheme is inconsistent beyond the one-loop order in perturbation theory. In this paper, we clarify the reason for this inconsistency by studying the perturbative expansion of the vector current correlator in one-flavor QED through three-loop order. We develop a simple, practical way to fix the four-dimensional helicity scheme using the idea of dimensional reconstruction, and demonstrate its application in several illustrative examples.

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Radja Boughezal, Kirill Melnikov, Frank Petriello. 2011-06-27. The four-dimensional helicity scheme and dimensional reconstruction. https://doi.org/10.1103/physrevd.84.034044

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