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Efficiency improvements for the numerical computation of NLO corrections

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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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Authors and Affiliations

  1. Institut für Physik, Universität Mainz, D-55099, Mainz, Germany

    Sebastian Becker, Christian Reuschle & Stefan Weinzierl

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  1. Sebastian Becker
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  2. Christian Reuschle
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  3. Stefan Weinzierl
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Correspondence to Stefan Weinzierl.

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ArXiv ePrint: 1205.2096

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Becker, S., Reuschle, C. & Weinzierl, S. Efficiency improvements for the numerical computation of NLO corrections. J. High Energ. Phys. 2012, 90 (2012). https://doi.org/10.1007/JHEP07(2012)090

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