{
  "abstract": "The Fundamental Metallicity Relation (FMR) extends the mass-metallicity relation (MZR) by including star formation rate (SFR) as a third parameter. At fixed stellar mass, galaxies with higher SFRs tend to have lower gas-phase metallicities. We investigate the physical origin of the FMR in the context of episodic star formation (Gui et al. 2026, paper I of this series) by tracing the evolution histories of 8,979 central star-forming galaxies selected at $z=0$ in TNG100 back to $z=1$. We find that the overall MZR scatter at $z=0$ ($\\sim0.11$ dex) comprises both long-lived differences among galaxies ($\\sim0.09$ dex) and temporal fluctuations within individual galaxies ($\\sim 0.07$ dex). The galaxy-to-galaxy component shows an anticorrelation between SFR and gas-phase metallicity, as shown by the observed FMR. As for the consequence from temporal fluctuation, we track individual histories and stack the upward and downward SFR phases of a refined sample. Time-shift analysis and stacked histories show a well-behaved sequence in which the cold non-star-forming gas reservoir increases (decreases) first, followed by a decrease (increase) in gas-phase metallicity and then a rise (decline) in SFR. This ordering is consistent with a physical scenario where metal-poor gas first replenishes the cold reservoir and dilutes the gas before SFR rises to the peak, followed by feedback-driven gas heating/removal, resulting in a shift in metallicity from dilution to enrichment as SFR decreases towards the valley. This naturally explains the anticorrelation between the SFR and gas-phase metallicities as indicated by the observed FMR.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2611.03645",
  "author_total": 5,
  "authors": [
    {
      "name": "Xuelun Mei"
    },
    {
      "name": "Dandan Xu"
    },
    {
      "name": "Cheng Li"
    },
    {
      "name": "Yuqian Gui"
    },
    {
      "name": "Haoyi Wang"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/26y23ry48ew0j.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2611.03645",
  "fulltext_url": null,
  "id": "26y23ry48ew0j",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2611.03645",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.GA"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2611.03645",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/26y23ry48ew0j.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T12:21:04Z",
      "native_id": "2611.03645",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2611.03645"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "Episodic Star Formation - II. The Origin of the Fundamental Metallicity Relation",
  "title_text": "Episodic Star Formation - II. The Origin of the Fundamental Metallicity Relation",
  "type": "preprint",
  "updated_at": "2026-11-05T15:20:21Z",
  "url": "https://research.draconitic.com/paper/26y23ry48ew0j",
  "venue": "arXiv",
  "versions": []
}