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arXiv · 1101.5595

Golem95C: A library for one-loop integrals with complex masses

G. Cullen·J. -Ph. Guillet·G. Heinrich·T. Kleinschmidt·E. Pilon·T. Reiter·M. Rodgers
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Abstract

We present a program for the numerical evaluation of scalar integrals and tensor form factors entering the calculation of one-loop amplitudes which supports the use of complex masses in the loop integrals. The program is built on an earlier version of the golem95 library, which performs the reduction to a certain set of basis integrals using a formalism where inverse Gram determinants can be avoided. It can be used to calculate one-loop amplitudes with arbitrary masses in an algebraic approach as well as in the context of a unitarity-inspired numerical reconstruction of the integrand.

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G. Cullen, J. -Ph. Guillet, G. Heinrich, T. Kleinschmidt, E. Pilon, T. Reiter, M. Rodgers. 2011-01-28. Golem95C: A library for one-loop integrals with complex masses. https://doi.org/10.1016/j.cpc.2011.05.015

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