{
  "abstract": "In this study, we investigate the spectral signatures of neutral hydrogen Lyman-$α$ absorption arising from the warm-hot gas component of the circumgalactic medium (CGM) around $z=0$ Milky Way (MW)-like galaxies using the high-resolution TNG50 cosmological simulation. We used synthetic absorption spectra to identify and characterise coronal broad Ly$α$ absorbers (CBLAs), which represent H I absorption features produced by the warm-hot CGM at temperatures above $10^5$ K. Our study implies that CBLAs have a significant absorption cross-section, $f_c$, around MW-like galaxies. Based on an analysis of 75 sightlines intersecting the CGM of 15 galaxies in the mass range $10^{11.7} M_{\\odot} \\leq M_{200} \\leq 10^{12.3} M_{\\odot}$, we find $f_c \\approx 0.8$ for $\\log N_{\\rm HI} \\geq 13$, where CBLAs span a total column-density range $\\log N_{\\rm HI}=11.6-15.4$. Therefore, CBLAs provide a significant contribution to the overall H I optical depth in the CGM with $\\sim 50\\%$ of the CGM absorbers being dominated by CBLA absorption. Furthermore, we find that CBLAs trace warm-hot gas in a temperature range $T=10^{5.2-6.4}$ K, which accounts for $\\sim 7\\%$ of the overall baryon budget in the TNG50 galaxies and $\\sim 25\\%$ of the total CGM mass. Finally, we identify a population of strong CBLAs that exhibit substantial H I column densities up to $\\log N_{\\rm HI}=14.9$. This population represents a new absorber class tracing massive warm-hot circumgalactic structures at large radial distances. In conclusion, our study demonstrates that CBLAs represent an important absorber class that needs to be considered when interpreting the H I absorption signatures from the multi-phase CGM of MW-like galaxies at low redshift.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2606.04083",
  "author_total": 5,
  "authors": [
    {
      "name": "P. Aparicio Marcos"
    },
    {
      "name": "P. Richter"
    },
    {
      "name": "M. Sparre"
    },
    {
      "name": "F. Rünger"
    },
    {
      "name": "D. Nelson"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bw05pgrerbqmf.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2606.04083",
  "fulltext_url": null,
  "id": "bw05pgrerbqmf",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2606.04083",
  "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.GA"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2606.04083",
  "pmcid": null,
  "pmid": null,
  "published": "2026-06-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/bw05pgrerbqmf.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:53Z",
      "native_id": "2606.04083",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2606.04083"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "Studying the absorption signatures of H I Lyman-α in the warm-hot circumgalactic medium with TNG50",
  "title_text": "Studying the absorption signatures of H I Lyman-α in the warm-hot circumgalactic medium with TNG50",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:53Z",
  "url": "https://research.draconitic.com/paper/bw05pgrerbqmf",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1051/0004-6361/202659480",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}