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arXiv · hep-th/9911211

Split dimensional regularization for the Coulomb gauge at two loops

G. Heinrich·G. Leibbrandt
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Abstract

We evaluate the coefficients of the leading poles of the complete two-loop quark self-energy Σ(p) in the Coulomb gauge. Working in the framework of split dimensional regularization, with complex regulating parameters σand n/2-σfor the energy and space components of the loop momentum, respectively, we find that split dimensional regularization leads to well-defined two-loop integrals, and that the overall coefficient of the leading pole term for Σ(p) is strictly local. Extensive tables showing the pole parts of one- and two-loop Coulomb integrals are given. We also comment on some general implications of split dimensional regularization, discussing in particular the limit σ\to 1/2 and the subleading terms in the epsilon-expansion of noncovariant integrals.

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G. Heinrich, G. Leibbrandt. 1999-11-29. Split dimensional regularization for the Coulomb gauge at two loops. https://doi.org/10.1016/s0550-3213(00)00078-x

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