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    "story_id": "mp-2026-09-13-026",
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    "headline": "An Almost-Dark Galaxy Landed on the Other Branch of the Equation",
    "slug": "an-almost-dark-galaxy-landed-on-the-other-branch-of-the-equation",
    "dek": "A separability framework for dark-matter-deficient galaxies predicts a conjugate baryon-depleted regime testable with kinematics and globular clusters.",
    "summary": "A separability framework for dark-matter-deficient galaxies predicts a conjugate baryon-depleted regime testable with kinematics and globular clusters.",
    "body_text": "A theoretical extension of the dark-matter–baryon separability condition admits a branch where baryons are preferentially depleted rather than dark matter. Using the recently reported almost-dark galaxy TTT J1237327+143535 as a worked example, the authors derive relationships among line-of-sight velocity dispersion, dynamical mass, enclosed baryon fraction and mass-to-light ratio as the unknown progenitor ratio varies. They also connect the inferred halo to an expected globular-cluster population. Future stellar-kinematic, gas and cluster measurements are needed to test whether the galaxy actually occupies that branch.",
    "why_it_matters": "A separability framework for dark-matter-deficient galaxies predicts a conjugate baryon-depleted regime testable with kinematics and globular clusters.",
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    "importance": 7,
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    "first_published_at": "2026-09-13T09:00:00.000-04:00",
    "modified_at": "2026-09-13T09:00:00.000-04:00",
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    "tags": [
      "dark matter",
      "galaxies",
      "dynamics"
    ],
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  "sources": [
    {
      "source_id": "source-2026-09-13-015",
      "title": "arXiv preprint 2609.10661",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2609.10661",
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      "accessed_at": "2026-09-13T08:24:00.000-04:00",
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  "publisher": {
    "name": "The Machine Press",
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    "title": "An Almost-Dark Galaxy Landed on the Other Branch of the Equation",
    "publisher": "The Machine Press",
    "published_at": "2026-09-13T09:00:00.000-04:00",
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