{
  "abstract": "We study gravitational-wave production during perturbative reheating without assuming instantaneous thermalization of the inflaton decay products. The injected energetic particles thermalize through an in-medium cascade of nearly collinear splittings subject to the Landau-Pomeranchuk-Migdal effect and are ultimately isotropized by elastic scatterings near the thermal scale. The non-thermal hard population present before complete thermalization produces an additional gravitational-wave component through hard-soft scatterings, with $Ω_{\\mathrm{GW}}\\propto f^{1/2}$ below the injection-scale turnover. The same isotropization erases the directional information underlying the vacuum $1/k$ bremsstrahlung soft pole, changing the deep-infrared spectrum from $Ω_{\\mathrm{GW}}\\propto f$ to $Ω_{\\mathrm{GW}}\\propto f^3$.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.01480",
  "author_total": 2,
  "authors": [
    {
      "name": "Kyohei Mukaida"
    },
    {
      "name": "Tenta Tsuji"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/4d2j76hwfjp46.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.01480",
  "fulltext_url": null,
  "id": "4d2j76hwfjp46",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.01480",
  "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",
      "astro-ph.CO"
    ],
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "arxiv",
      "hep-th"
    ],
    [
      "openalex",
      "3103|Cosmology and Gravitation Theories"
    ]
  ],
  "openalex": "W7206172433",
  "pdf_url": "https://arxiv.org/pdf/2609.01480",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/4d2j76hwfjp46.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:00Z",
      "native_id": "2609.01480",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.01480"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "physics",
      "origin": "arxiv:hep-ph",
      "subfield": "high-energy"
    }
  ],
  "title": "Gravitational Waves from Reheating beyond Instantaneous Thermalization",
  "title_text": "Gravitational Waves from Reheating beyond Instantaneous Thermalization",
  "type": "preprint",
  "updated_at": "2026-10-30T12:18:00Z",
  "url": "https://research.draconitic.com/paper/4d2j76hwfjp46",
  "venue": "arXiv",
  "versions": []
}