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arXiv · 1706.06218

Combining states without scale hierarchies with ordered parton showers

Nadine Fischer·Stefan Prestel
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Abstract

We present a parameter-free scheme to combine fixed-order multi-jet results with parton-shower evolution. The scheme produces jet cross sections with leading-order accuracy in the complete phase space of multiple emissions, resumming large logarithms when appropriate, while not arbitrarily enforcing ordering on momentum configurations beyond the reach of the parton-shower evolution equation. This requires the development of a matrix-element correction scheme for complex phase-spaces including ordering conditions as well as a systematic scale-setting procedure for unordered phase-space points. The resulting algorithm does not require a merging-scale parameter. We implement the new method in the Vincia framework and compare to LHC data.

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Nadine Fischer, Stefan Prestel. 2017-09-17. Combining states without scale hierarchies with ordered parton showers. https://doi.org/10.1140/epjc%2Fs10052-017-5160-7

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