Year: 2024
Type: article
Abstract: A bstract In this work, we revisit unweighted event generation for multi-parton tree-level processes in massless QCD. We introduce a two-step approach, in which initially unweighted events are generated at leading-colour (LC) accuracy, followed by a reweighting of these events to full-colour (FC) accuracy and applying an additional unweighting cycle. This method leverages the simple structure of LC integrands, enabling optimized phase-space parameterisations and resulting in high primary unweighting efficiencies, ranging from the percent level for 2 → 4 processes to the per-mille level for 2 → 7 processes. Given that the LC-accurate matrix elements closely approximate the FC-accurate ones, the secondary unweighting efficiencies exceed 50%. Our results suggest that this two-step approach offers an efficient alternative to direct event generation at FC accuracy.
Source: Journal of High Energy Physics
Authors: Rikkert Frederix, Timea Vitos
Institutions: Lund University, Eötvös Loránd University, Uppsala University
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
Funder: Vetenskapsrådet
OpenAlex ID: W4405979945