{
  "id": "2405.06631",
  "version": "v1",
  "published": "2024-05-10T17:48:16.000Z",
  "updated": "2024-05-10T17:48:16.000Z",
  "title": "The Sunburst Arc with JWST: III. An Abundance of Direct Chemical Abundances",
  "authors": [
    "Brian Welch",
    "T. Emil Rivera-Thorsen",
    "Jane Rigby",
    "Taylor Hutchison",
    "Grace M. Olivier",
    "Danielle A. Berg",
    "Keren Sharon",
    "Hakon Dahle",
    "M. Riley Owens",
    "Matthew B. Bayliss",
    "Gourav Khullar",
    "John Chisholm",
    "Matthew Hayes",
    "Keunho J. Kim"
  ],
  "comment": "15 pages, 4 figures, 3 tables. Submitted to ApJ",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "We measure the gas-phase abundances of the elements He, N, O, Ne, S, Ar, and Fe in the Lyman-continuum emitting region of the Sunburst Arc, a highly magnified galaxy at redshift $z=2.37$. We detect the temperature-sensitive auroral lines [SII]$\\lambda\\lambda4069,4076$, [OII]$\\lambda\\lambda7320,7330$, [SIII]$\\lambda6312$, [OIII]$\\lambda4363$, and [NeIII]$\\lambda3343$ in a stacked spectrum of 5 multiple images of the Lyman-continuum emitter (LCE), from which we directly measure the electron temperature in the low, intermediate, and high ionization zones. We also detect the density-sensitive doublets of [OII]$\\lambda\\lambda3727,3729$, [SII]$\\lambda\\lambda6717,6731, and [ArIV]$\\lambda\\lambda4713,4741$, which constrain the density in both the low- and high-ionization gas. With these temperature and density measurements, we measure gas-phase abundances with similar rigor as studies of local galaxies. We measure a gas-phase metallicity for the LCE of $12+\\log(\\textrm{O}/\\textrm{H}) = 7.97 \\pm 0.05$, and find an enhanced nitrogen abundance $\\log(\\textrm{N}/\\textrm{O}) = -0.65^{+0.16}_{-0.25}$. This nitrogen abundance is consistent with enrichment from a population of Wolf-Rayet stars, additional signatures of which are reported in a companion paper. Abundances of sulfur, argon, neon, and iron are consistent with local low-metallicity HII regions and low-redshift galaxies. This study represents the most complete chemical abundance analysis of a galaxy at Cosmic Noon to date, which enables direct comparisons between local HII regions and those in the distant universe.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2024-05-10T17:48:16.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "direct chemical abundances",
      "sunburst arc",
      "local low-metallicity hii regions",
      "high ionization zones",
      "complete chemical abundance analysis"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 15,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}