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    "story_id": "mp-2026-09-19-015",
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    "headline": "Long Gamma-Ray Bursts Doubled Their Supernova-Less Candidate List",
    "slug": "long-gamma-ray-bursts-doubled-their-supernova-less-candidate-list",
    "dek": "Two decades of Swift data produced a rate of 0.5 ± 0.2 events per cubic gigaparsec per year before beaming correction.",
    "summary": "Two decades of Swift data produced a rate of 0.5 ± 0.2 events per cubic gigaparsec per year before beaming correction.",
    "body_text": "A search below redshift 0.35 more than doubled the candidate set with robust supernova limits and distance scales. The small, heterogeneous sample spans star-forming, dusty and quiescent hosts; plausible beaming corrections remain compatible with several compact-merger channels but do not establish one origin.",
    "why_it_matters": "Two decades of Swift data produced a rate of 0.5 ± 0.2 events per cubic gigaparsec per year before beaming correction.",
    "limitations": [
      "The small, heterogeneous sample spans star-forming, dusty and quiescent hosts; plausible beaming corrections remain compatible with several compact-merger channels but do not establish one origin."
    ],
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    "first_published_at": "2026-09-19T09:00:00.000-04:00",
    "modified_at": "2026-09-19T09:00:00.000-04:00",
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        "text": "Two decades of Swift data produced a rate of 0.5 ± 0.2 events per cubic gigaparsec per year before beaming correction.",
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        "qualification": "The small, heterogeneous sample spans star-forming, dusty and quiescent hosts; plausible beaming corrections remain compatible with several compact-merger channels but do not establish one origin."
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    "source_ids": [
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    "tags": [
      "gamma-ray bursts",
      "supernovae",
      "Swift"
    ],
    "image_url": null,
    "corrections": []
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  "sources": [
    {
      "source_id": "source-2026-09-19-017",
      "title": "arXiv preprint 2609.20787",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2609.20787",
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      "source_type": "primary_research",
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      "published_at": "2026-09-17T13:52:57.000-04:00",
      "accessed_at": "2026-09-19T08:30:21.326-04:00",
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    "name": "The Machine Press",
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  "cite_this_report": {
    "title": "Long Gamma-Ray Bursts Doubled Their Supernova-Less Candidate List",
    "publisher": "The Machine Press",
    "published_at": "2026-09-19T09:00:00.000-04:00",
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