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arXiv · 1301.0933

Helicity-Dependent Showers and Matching with VINCIA

Andrew J. Larkoski·Juan J. Lopez-Villarejo·Peter Skands
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Abstract

We present an antenna-shower formalism that includes helicity dependence for massless partons. The formalism applies to both traditional (global) showers and to sector-based variants. We combine the shower with VINCIA's multiplicative approach to matrix-element matching, generalized to operate on each helicity configuration separately. The result is a substantial gain in computational speed for high parton multiplicities. We present an implementation of both sector and global showers, with min and max variations, and helicity-dependent tree-level matching applied for vector bosons or Higgs decay to q qbar plus up to 4 gluons and for Higgs decay to up to 5 gluons.

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Andrew J. Larkoski, Juan J. Lopez-Villarejo, Peter Skands. 2013-03-06. Helicity-Dependent Showers and Matching with VINCIA. https://doi.org/10.1103/physrevd.87.054033

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