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arXiv · 1407.0087

COLLIER -- A fortran-library for one-loop integrals

Ansgar Denner·Stefan Dittmaier·Lars Hofer
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Abstract

We introduce the fortran-library COLLIER for the numerical evaluation of one-loop scalar and tensor integrals in perturbative relativistic quantum field theories. Important features are the implementation of dedicated methods to achieve numerical stability for 3- and 4-point tensor integrals, the support of complex masses for internal particles, and the possibility to choose between dimensional and mass regularization for infrared singularities. COLLIER supports one-loop N-point functions up to currently N=6 and has been tested in various NLO QCD and EW calculations.

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Ansgar Denner, Stefan Dittmaier, Lars Hofer. 2014-07-01. COLLIER -- A fortran-library for one-loop integrals. https://arxiv.org/abs/1407.0087

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