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

نویسنده

  • Stefan Dittmaier
چکیده

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. August 2003

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تاریخ انتشار 2003