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arXiv · 1606.08753

Reweighting QCD matrix-element and parton-shower calculations

Enrico Bothmann·Marek Schönherr·Steffen Schumann
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Abstract

We present the implementation and validation of the techniques used to efficiently evaluate parametric and perturbative theoretical uncertainties in matrix-element plus parton-shower simulations within the Sherpa event-generator framework. By tracing the full $α_s$ and PDF dependences, including the parton-shower component, as well as the fixed-order scale uncertainties, we compute variational event weights on-the-fly, thereby greatly reducing the computational costs to obtain theoretical-uncertainty estimates.

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Enrico Bothmann, Marek Schönherr, Steffen Schumann. 2016-11-10. Reweighting QCD matrix-element and parton-shower calculations. https://doi.org/10.1140/epjc%2Fs10052-016-4430-0

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