{
  "abstract": "Virgo is the nearest cool core (CC) galaxy cluster, and is archetypal of the class of X-ray weak CCs. Despite the X-ray continuum implying a large cooling rate ($\\gtrsim 10\\,{\\rm M_{\\odot}\\,yr^{-1}}$), measurements of cooler gas phases, dust, and star formation show almost no cooling outside the M87 nucleus. It is also known that M87$^{\\ast}$ is a prodigious source of cosmic ray (CR) leptons observed in radio and $γ$-rays, and recent radio observations have shown that the M87 radio halo is low-frequency and its spectral index steepens rapidly away from the injection region+jets, consistent with an aging, low-energy CR population. We demonstrate that coupling X-ray and radio to newer Faraday rotation limits on the magnetic field, this implies the CRs within the CC radius ($\\lesssim 40$kpc) must contribute significantly to the total pressure and soft X-ray emission, through a combination of Coulomb heating the gas and inverse-Compton (IC) scattering microwave background photons to $\\sim$keV. We show this can explain the apparent correspondence between jet/radio power and X-ray cooling luminosity, and why the X-ray inferred cooling rate appears much larger than otherwise observed. This would also explain why the central X-ray inferred metallicity at $\\lesssim 10\\,$kpc appears to be suppressed relative to the UV/optical inferred metallicity (in a wavelength-dependent manner). Compared to more extreme radio+X-ray sources like Perseus, we find the observations require a softer 'escaping' CR spectrum (escaping or accelerated outside $\\gtrsim 1\\,$kpc from M87$^{\\ast}$).",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.03881",
  "author_total": 5,
  "authors": [
    {
      "name": "Philip F. Hopkins"
    },
    {
      "name": "Emily M. Silich"
    },
    {
      "name": "Jack Sayers"
    },
    {
      "name": "Sam B. Ponnada"
    },
    {
      "name": "Isabel S. Sands"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6tasd9xp2c5je.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.03881",
  "fulltext_url": null,
  "id": "6tasd9xp2c5je",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.03881",
  "language": null,
  "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"
    ],
    [
      "arxiv",
      "astro-ph.GA"
    ],
    [
      "arxiv",
      "astro-ph.HE"
    ],
    [
      "openalex",
      "3106|Astrophysics and Cosmic Phenomena"
    ]
  ],
  "openalex": "W7220690704",
  "pdf_url": "https://arxiv.org/pdf/2610.03881",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/6tasd9xp2c5je.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:01Z",
      "native_id": "2610.03881",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.03881"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "The Virgo Cluster as a Case Study for Ancient Cosmic Ray Halos in Radio and X-rays",
  "title_text": "The Virgo Cluster as a Case Study for Ancient Cosmic Ray Halos in Radio and X-rays",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:01Z",
  "url": "https://research.draconitic.com/paper/6tasd9xp2c5je",
  "venue": "arXiv",
  "versions": []
}