{
  "abstract": "The matrix element method (MEM) provides a fully probabilistic approach to confront experimental events with theory, retaining all correlations in the scattering matrix element. While leading-order MEM is widely used and automated, extending it to next-to-leading order (NLO) in QCD is challenging due to infrared divergences, negative weights, extra final-state partons, and multi-dimensional phase-space integration. We demonstrate that the POWHEG method offers a practical path to MEM at NLO accuracy. By projecting real-emission events onto Born kinematics via the mappings inherited from the $\\tilde{B} (Φ)$ function, our method consistently includes the hardest QCD radiation while preserving the NLO-accurate normalization. As a proof of concept, we apply the method to fully leptonic $W^+W^-$ production in the Standard Model effective field theory (SMEFT), considering a CP-even dimension-six triple-gauge-boson operator. At the parton level, the resulting NLO MEM exploits spin and polarization correlations in the final-state lepton kinematics, yielding enhanced discrimination between the SM and BSM hypotheses compared with conventional cut-and-count observables. Our results demonstrate the feasibility of incorporating NLO QCD corrections into the MEM and establish a framework for future applications to a broad range of collider processes.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2606.11083",
  "author_total": 5,
  "authors": [
    {
      "name": "Ulrich Haisch"
    },
    {
      "name": "Jakob Linder"
    },
    {
      "name": "Luc Schnell"
    },
    {
      "name": "Marius Wiesemann"
    },
    {
      "name": "Giulia Zanderighi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7j2f762ng2dy9.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2606.11083",
  "fulltext_url": null,
  "id": "7j2f762ng2dy9",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2606.11083",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "hep-ex"
    ],
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "openalex",
      "3106|Particle physics theoretical and experimental studies"
    ]
  ],
  "openalex": "W7164125907",
  "pdf_url": "https://arxiv.org/pdf/2606.11083",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-12",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/7j2f762ng2dy9.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:06Z",
      "native_id": "2606.11083",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2606.11083"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ex",
      "subfield": "high-energy"
    }
  ],
  "title": "Matrix element method at NLO: A fine proof of concept in POWHEG",
  "title_text": "Matrix element method at NLO: A fine proof of concept in POWHEG",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:06Z",
  "url": "https://research.draconitic.com/paper/7j2f762ng2dy9",
  "venue": "arXiv",
  "versions": []
}