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Explicit results for all orders of the epsilon-expansion of certain massive and massless diagrams

A. I. Davydychev
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Abstract

An arbitrary term of the epsilon-expansion of dimensionally regulated off-shell massless one-loop three-point Feynman diagram is expressed in terms of log-sine integrals related to the polylogarithms. Using magic connection between these diagrams and two-loop massive vacuum diagrams, the epsilon-expansion of the latter is also obtained, for arbitrary values of the masses. The problem of analytic continuation is also discussed.

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A. I. Davydychev. 1999-10-04. Explicit results for all orders of the epsilon-expansion of certain massive and massless diagrams. https://doi.org/10.1103/physrevd.61.087701

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