{
  "abstract": "The dead-cone effect reflects the mass dependence of QCD radiation from heavy quarks. We investigate this phenomenon from charm and bottom to top quarks using two-dimensional angular distributions and single-particle inclusive momentum spectra. The angular distributions illustrate the depletion of radiation around the heavy-quark direction, while the momentum spectra provide a quantitative observable of the effect. For charm and bottom jets, fragmentation functions reconstructed from LEP data at the $Z$ pole exhibit a strong suppression of high-momentum particles, quantitatively described within the Modified Leading Logarithmic Approximation of perturbative QCD. The analysis is extended to $\\sqrt{s}=1$ TeV using Monte Carlo simulations. A hypothetical stable-top sample isolates the primary top-quark radiation pattern, whereas the physical decay $t\\to bW$ introduces coherent radiation from the $tb$ colour dipole, obscuring the primary dead cone. By exploiting the dependence on the $b$-quark emission angle $Θ_b$, we reconstruct the primary top-quark parton momentum spectrum through extrapolation to $Θ_b\\to0$. In contrast, the small-angle gluon and parton distributions do not converge to the stable-top dead-cone pattern because of radiation from the decay $b$ quark. These findings establish the inclusive momentum spectrum as a robust quantitative observable of the top-quark dead-cone effect and provide a unified description of mass-dependent QCD radiation from charm to top.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.20164",
  "author_total": 3,
  "authors": [
    {
      "name": "Redamy Perez-Ramos"
    },
    {
      "name": "Stefan Kluth"
    },
    {
      "name": "Wolfgang Ochs"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/b019nbj0hwhtr.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.20164",
  "fulltext_url": null,
  "id": "b019nbj0hwhtr",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.20164",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "hep-ex"
    ],
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "openalex",
      "3106|Particle physics theoretical and experimental studies"
    ]
  ],
  "openalex": "W7222270071",
  "pdf_url": "https://arxiv.org/pdf/2610.20164",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-14",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/b019nbj0hwhtr.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:31Z",
      "native_id": "2610.20164",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.20164"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ex",
      "subfield": "high-energy"
    }
  ],
  "title": "The dead-cone effect in charm, bottom and top quark jets in angular and momentum space",
  "title_text": "The dead-cone effect in charm, bottom and top quark jets in angular and momentum space",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:31Z",
  "url": "https://research.draconitic.com/paper/b019nbj0hwhtr",
  "venue": "arXiv",
  "versions": []
}