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arXiv · 1904.11866

Logarithmic Accuracy of Angular-Ordered Parton Showers

Gavin Bewick·Silvia Ferrario Ravasio·Peter Richardson·Michael H. Seymour
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Abstract

We study the logarithmic accuracy of angular-ordered parton showers by considering the singular limits of multiple emission matrix elements. This allows us to consider different choices for the evolution variable and propose a new choice which has both the correct logarithmic behaviour and improved performance away from the singular regions. In particular the description of $e^+e^-$ event shapes in the non-logarithmic region is significantly improved.

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Gavin Bewick, Silvia Ferrario Ravasio, Peter Richardson, Michael H. Seymour. 2019-04-26. Logarithmic Accuracy of Angular-Ordered Parton Showers. https://arxiv.org/abs/1904.11866

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