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arXiv · 1205.2096

Efficiency improvements for the numerical computation of NLO corrections

Sebastian Becker·Christian Reuschle·Stefan Weinzierl
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Abstract

In this paper we discuss techniques, which lead to a significant improvement of the efficiency of the Monte Carlo integration, when one-loop QCD amplitudes are calculated numerically with the help of the subtraction method and contour deformation. The techniques discussed are: holomorphic and non-holomorphic division into sub-channels, optimisation of the integration contour, improvement of the ultraviolet subtraction terms, importance sampling and antithetic variates in loop momentum space, recurrence relations.

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Sebastian Becker, Christian Reuschle, Stefan Weinzierl. 2012-06-25. Efficiency improvements for the numerical computation of NLO corrections. https://doi.org/10.1007/jhep07(2012)090

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