{
  "id": "2104.11756",
  "version": "v1",
  "published": "2021-04-23T18:00:20.000Z",
  "updated": "2021-04-23T18:00:20.000Z",
  "title": "Cosmic Star-Formation History Measured at 1.4 GHz",
  "authors": [
    "A. M. Matthews",
    "J. J. Condon",
    "W. D. Cotton",
    "T. Mauch"
  ],
  "comment": "19 pages, 13 figures; accepted for publication in ApJ",
  "categories": [
    "astro-ph.GA",
    "astro-ph.CO"
  ],
  "abstract": "We matched the 1.4 GHz local luminosity functions of star-forming galaxies (SFGs) and active galactic nuclei to the 1.4 GHz differential source counts from $0.25 \\ \\mu\\mathrm{Jy}$ to 25 Jy using combinations of luminosity and density evolution. We present the most robust and complete local far-infrared (FIR)/radio luminosity correlation to date in a volume-limited sample of $\\approx 4.3 \\times 10^3$ nearby SFGs, finding that it is very tight but distinctly sub-linear: $L_\\mathrm{FIR} \\propto L_\\mathrm{1.4\\,GHz}^{0.85}$. If the local FIR/radio correlation does not evolve, the evolving 1.4 GHz luminosity function of SFGs yields the evolving star-formation rate density (SFRD) $\\psi (M_\\odot \\ \\mathrm{year}^{-1} \\ \\mathrm{Mpc}^{-3}$) as a function of time since the big bang. The SFRD measured at 1.4 GHz grows rapidly at early times, peaks at \"cosmic noon\" when $t \\approx 3 \\ \\mathrm{Gyr}$ and $z \\approx 2$, and subsequently decays with an $e$-folding time scale $\\tau = 3.2 \\ \\mathrm{Gyr}$. This evolution is similar to, but somewhat stronger than, SFRD evolution estimated from UV and FIR data.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2021-04-23T18:00:20.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "cosmic star-formation history",
      "ghz differential source counts",
      "ghz local luminosity functions",
      "local fir/radio correlation",
      "evolving star-formation rate density"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 19,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}