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arXiv · 0812.2134

A complete reduction of one-loop tensor 5- and 6-point integrals

Th. Diakonidis·J. Fleischer·J. Gluza·K. Kajda·T. Riemann·J. B. Tausk
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Abstract

We perform a complete analytical reduction of general one-loop Feynman integrals with five and six external legs for tensors up to rank R=3 and 4, respectively. An elegant formalism with extensive use of signed minors is developed for the cancellation of inverse Gram determinants. The 6-point tensor functions of rank R are expressed in terms of 5-point tensor functions of rank R-1, and the latter are reduced to scalar four-, three-, and two-point functions. The resulting compact formulae allow both for a study of analytical properties and for efficient numerical programming. They are implemented in Fortran and Mathematica.

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Th. Diakonidis, J. Fleischer, J. Gluza, K. Kajda, T. Riemann, J. B. Tausk. 2008-12-11. A complete reduction of one-loop tensor 5- and 6-point integrals. https://doi.org/10.1103/physrevd.80.036003

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