{
  "abstract": "Increasingly deep, confusion-limited radio surveys have pushed direct radio source-count measurements down to tens of $μ$Jy at 1.4 GHz. Confusion-noise P(D) analyses extend the statistical counts to below $1\\,\\mathrm{μJy}$. Radio source counts have allowed for constraints on the radio-derived star formation rate density (SFRD) history through models of the backwards evolution of the local radio luminosity function, using the radio-FIR correlation, $q \\propto \\log(L_{\\mathrm{FIR}}/L_{1.4})$, to convert radio luminosities to FIR luminosities and hence star-formation rates. Recent deep radio source counts from MeerKAT suggest a potential tension in the SFRD history between radio and UV/IR measurements at $1\\lesssim z\\lesssim 2$. This corresponds to a $\\gtrsim 3σ$ discrepancy between the predicted and measured source counts near the star forming galaxy source count $S^2n(S)$ peak of ${\\sim}30\\,\\mathrm{μJy}$ under both a pure luminosity (PLE) and combined luminosity and density evolution (LADE). We consider what the requirement of agreement between radio source counts and the observed UV/IR SFRD indicates about the redshift evolution of the radio-FIR correlation and its intrinsic scatter out to $z=3$. We introduce a radio-luminosity based parameterization to $q_{\\mathrm{FIR}}(z)$ based on changing thermal radio fractions alone that agrees with the observed stellar-mass dependent $q_{\\mathrm{FIR}}(z)$ better than a non-evolving or decreasing $q_{\\mathrm{FIR}}(z)$. Despite this, we find that a decreasing $q_{\\mathrm{FIR}}(z)$ at fixed radio luminosity provides better agreement between source counts and the observed SFRD, while a $q_{\\mathrm{FIR}}(z)$ that breaks down due to cosmic ray losses requires an intrinsic scatter up to $σ_q\\approx 0.3\\,\\mathrm{dex}$.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2606.02717",
  "author_total": 4,
  "authors": [
    {
      "name": "Tirth D. Surti"
    },
    {
      "name": "Vikram Ravi"
    },
    {
      "name": "Allison Matthews"
    },
    {
      "name": "Viviana A. Rosero"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0vkhpjvwe1m7y.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2606.02717",
  "fulltext_url": null,
  "id": "0vkhpjvwe1m7y",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2606.02717",
  "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.GA"
    ],
    [
      "openalex",
      "3103|Galaxies: Formation, Evolution, Phenomena"
    ]
  ],
  "openalex": "W7163386438",
  "pdf_url": "https://arxiv.org/pdf/2606.02717",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/0vkhpjvwe1m7y.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:31Z",
      "native_id": "2606.02717",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2606.02717"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "The Radio-FIR Correlation in the Context of Deep Radio Source Counts",
  "title_text": "The Radio-FIR Correlation in the Context of Deep Radio Source Counts",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:31Z",
  "url": "https://research.draconitic.com/paper/0vkhpjvwe1m7y",
  "venue": "arXiv",
  "versions": []
}