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Separation of soft and collinear singularities from one-loop N-point integrals

Stefan Dittmaier
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Abstract

The soft and collinear singularities of general scalar and tensor one-loop N-point integrals are worked out explicitly. As a result a simple explicit formula is given that expresses the singular part in terms of 3-point integrals. Apart from predicting the singularities, this result can be used to transfer singular one-loop integrals from one regularization scheme to another or to subtract soft and collinear singularities from one-loop Feynman diagrams directly in momentum space.

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Stefan Dittmaier. 2003-08-25. Separation of soft and collinear singularities from one-loop N-point integrals. https://doi.org/10.1016/j.nuclphysb.2003.10.003

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