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arXiv · 1308.5605

Complete Nagy-Soper subtraction for next-to-leading order calculations in QCD

G. Bevilacqua·M. Czakon·M. Kubocz·M. Worek
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Abstract

We extend the Helac-Dipoles package with the implementation of a new subtraction formalism, first introduced by Nagy and Soper in the formulation of an improved parton shower. We discuss a systematic, semi-numerical approach for the evaluation of the integrated subtraction terms for both massless and massive partons, which provides the missing ingredient for a complete implementation. In consequence, the new scheme can now be used as part of a complete NLO QCD calculation for processes with arbitrary parton masses and multiplicities. We assess its overall performance through a detailed comparison with results based on Catani-Seymour subtraction. The importance of random polarization and color sampling of the external partons is also examined.

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G. Bevilacqua, M. Czakon, M. Kubocz, M. Worek. 2013-11-01. Complete Nagy-Soper subtraction for next-to-leading order calculations in QCD. https://doi.org/10.1007/jhep10(2013)204

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