{
  "id": "1910.08947",
  "version": "v1",
  "published": "2019-10-20T10:54:49.000Z",
  "updated": "2019-10-20T10:54:49.000Z",
  "title": "A search for heavy-metal stars: abundance analyses of hot subdwarfs with Subaru",
  "authors": [
    "N. Naslim",
    "C. S. Jeffery",
    "V. M. Woolf"
  ],
  "comment": "Accepted to publish in MNRAS",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "The discovery of extremely zirconium- and lead-rich surfaces amongst a small subgroup of hot subdwarfs has provoked questions pertaining to chemical peculiarity in hot star atmospheres and about their evolutionary origin. With only three known in 2014, a limited search for additional `heavy-metal' subdwarfs was initiated with the Subaru telescope. Five hot subdwarfs having intermediate to high surface enrichment of helium were observed at high-resolution and analyzed for surface properties and abundances. This paper reports the analyses of four of these stars. PG1559+048 and FBS 1749+373, having only intermediate helium enrichment, show strong lines of triply ionized lead. PG1559+048 also shows a strong overabundance of germanium and yttrium. With more helium-rich surfaces, Ton 414 and J17554+5012, do not show evidence of heavy-metal enrichment. This limited survey suggests that extreme enrichment of `heavy metals' by selective radiative levitation in hot subdwarf atmospheres is suppressed if the star is too helium-rich.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2019-10-20T10:54:49.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "abundance analyses",
      "heavy-metal stars",
      "hot star atmospheres",
      "intermediate helium enrichment",
      "high surface enrichment"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}