{
  "abstract": "Tree-level matrix elements sit at the heart of collider event generation, but their cost rises rapidly just where additional resolved radiation becomes most important. We present pyAmpliCol, a public generator aimed at extending the practical reach of colour-resolved matrix elements to higher multiplicities. It builds on the colour-ordered, off-shell-current strategy of AmpliCol, providing fast access to individual leading-colour flows while retaining the option of next-to-leading or exact full colour. The latter introduces its own high-multiplicity bottleneck: the dense interference of factorially many colour orderings. pyAmpliCol addresses this contraction with a fast Fourier transform on the symmetric group, preserving the exact colour result while avoiding the direct pairwise sum. Representative full-colour benchmarks demonstrate substantial speedups over the reference calculations considered here. It supports Standard Model processes and a broad class of UFO models, selected or summed helicities, vectorised evaluation and controllable numerical precision. It further provides colour- and spin-correlated Born quantities and tree-level colour connections at arbitrary perturbative order, opening the same framework to local subtraction and other higher-order applications. Together, these capabilities connect high-multiplicity matrix elements to their use in event generation, merging, parton showers and precision calculations within a single generator.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.10729",
  "author_total": 6,
  "authors": [
    {
      "name": "Rikkert Frederix"
    },
    {
      "name": "Valentin Hirschi"
    },
    {
      "name": "Lucien Huber"
    },
    {
      "name": "Shahriar Iravanian"
    },
    {
      "name": "Ben Ruijl"
    },
    {
      "name": "Timea Vitos"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/af5td1q36r831.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.10729",
  "fulltext_url": null,
  "id": "af5td1q36r831",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.10729",
  "language": null,
  "licence": "CC0-1.0",
  "licence_label": "CC0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/publicdomain/zero/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "arxiv",
      "hep-th"
    ],
    [
      "openalex",
      "3106|Particle physics theoretical and experimental studies"
    ]
  ],
  "openalex": "W7221111146",
  "pdf_url": "https://arxiv.org/pdf/2610.10729",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-07",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/af5td1q36r831.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:54Z",
      "native_id": "2610.10729",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.10729"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ph",
      "subfield": "high-energy"
    }
  ],
  "title": "pyAmpliCol: fast tree-level matrix elements",
  "title_text": "pyAmpliCol: fast tree-level matrix elements",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:54Z",
  "url": "https://research.draconitic.com/paper/af5td1q36r831",
  "venue": "arXiv",
  "versions": []
}