{
  "abstract": "Cosmic filaments connect the nodes of the large-scale web and are thought to harbour a substantial fraction of the low-z baryon budget, yet a physically motivated framework for organising their diverse gas properties has been lacking. Here we show that the linear mass density $Λ$ = M_gas/L_fil, measured within the entropy radius r_K (the peak of the radial gas entropy profile) plays this role, analogous to mass in halo physics. Using TNG300-1 at z=0, we characterise the structural, thermodynamic, and chemical properties of 5637 filaments spanning more than two decades in $Λ$. Filaments form a continuous thermodynamic sequence with $Λ$, ranging from long, thin, cool, metal-poor structures to shorter, wider, hotter, and more enriched ones, with core temperatures spanning two orders of magnitude across the full WHIM window. The ratio of mass- to volume-weighted temperature reveals a shift in heat distribution: low-$Λ$ filaments have their hotter gas preferentially associated with denser material, whereas in high-$Λ$ filaments the hotter gas is diffuse. Well-defined scaling relations connect $Λ$ to temperature, electron density, pressure, entropy, and metallicity, with the T-$Λ$ scaling qualitatively consistent with gravitational heating. We present the first measurement of the gaseous linear mass density function, revealing a broad distribution with a flat low-$Λ$ regime and a steep exponential decline at high $Λ$, analogous to the halo mass function. The integrated Compton-y parameter $Y^{\\rm int}$ scales systematically with $Λ$, providing a tSZ proxy accessible to current surveys. Finally, galaxy richness per unit length correlates tightly with $Λ$ (Pearson r=0.80), enabling $Λ$-based classification of filaments from spectroscopic surveys alone and guiding targeted searches for the missing baryons in the cosmic web.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.26306",
  "author_total": 6,
  "authors": [
    {
      "name": "Daniela Galárraga-Espinosa"
    },
    {
      "name": "Daisuke Nagai"
    },
    {
      "name": "Isabel Medlock"
    },
    {
      "name": "Mathieu Langer"
    },
    {
      "name": "Nabila Aghanim"
    },
    {
      "name": "Kentaro Nagamine"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/c0seg2ffskqsh.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.26306",
  "fulltext_url": null,
  "id": "c0seg2ffskqsh",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.26306",
  "language": "en",
  "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",
      "astro-ph.CO"
    ],
    [
      "hal",
      "0.phys"
    ],
    [
      "hal",
      "1.phys.astr"
    ],
    [
      "openalex",
      "3103|Galaxies: Formation, Evolution, Phenomena"
    ]
  ],
  "openalex": "W7223070337",
  "pdf_url": "https://arxiv.org/pdf/2610.26306",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-19",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/c0seg2ffskqsh.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:30:52Z",
      "native_id": "2610.26306",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.26306"
    },
    {
      "first_seen": "2026-11-05T12:20:13Z",
      "native_id": "hal-05852943",
      "source": "hal",
      "url": "https://hal.science/hal-05852943v1"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "physics",
      "origin": "hal:0.phys",
      "subfield": "general"
    }
  ],
  "title": "Linear gas mass density: a unifying descriptor of Cosmic Filaments",
  "title_text": "Linear gas mass density: a unifying descriptor of Cosmic Filaments",
  "type": "preprint",
  "updated_at": "2026-11-06T12:20:44Z",
  "url": "https://research.draconitic.com/paper/c0seg2ffskqsh",
  "venue": "arXiv",
  "versions": []
}