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arXiv · 2310.04160

A new way of reducing negative weights in MC@NLO

Rikkert Frederix·Paolo Torrielli
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Abstract

We introduce a new technique, that we dub Born spreading, aimed at reducing the number of negative-weight $\mathbb S$ events in the MC@NLO matching of NLO calculations with parton-shower simulations. We show that such a technique, based on a re-distribution of Born matrix elements in the radiative phase space, achieves a sizeable reduction of negative-weight events at little computational cost. The method does not induce any biases in physical distributions.

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Rikkert Frederix, Paolo Torrielli. 2023-10-06. A new way of reducing negative weights in MC@NLO. https://arxiv.org/abs/2310.04160

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