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Some remarks on the epsilon-expansion of dimensionally regulated Feynman diagrams

A. I. Davydychev·M. Yu. Kalmykov
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Abstract

Some problems related to construction of the epsilon-expansion of dimensionally regulated Feynman integrals are discussed. For certain classes of diagrams, an arbitrary term of the epsilon-expansion can be expressed in terms of log-sine integrals related to the polylogarithms. It is shown how the analytic continuation of these functions can be constructed in terms of the generalized Nielsen polylogarithms.

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A. I. Davydychev, M. Yu. Kalmykov. 2000-05-31. Some remarks on the epsilon-expansion of dimensionally regulated Feynman diagrams. https://doi.org/10.1016/s0920-5632(00)00857-4

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