{
  "abstract": "We develop a new star formation model for galaxy simulations in which star-forming gas clumps are identified on-the-fly and converted into stars with an efficiency $ε_{\\rm SF}$ set by the clump surface density $Σ_{\\rm c}$, calibrated against radiation hydrodynamics simulations of star cluster formation. Applying this model to isolated disc galaxies embedded in haloes of $M_{\\rm h}=10^{9}$, $10^{10}$ and $10^{11}\\,\\mathrm{M_\\odot}$, with disc compactness corresponding to redshift $z=0$--$10$, we find that more compact discs form more massive and denser clumps. The maximum clump mass increases from $\\sim 10^{5}$ to $\\sim 10^{7}\\,\\mathrm{M_\\odot}$, and the fraction of clumps exceeding the surface density of $300\\,\\mathrm{M_\\odot\\,pc^{-2}}$ rises from $0.25$ to $0.38$ between $z=0$ and $10$ in $10^{10}\\,\\mathrm{M_\\odot}$ haloes. Star formation becomes correspondingly bursty, and the global star formation efficiency after three disc rotations increases from $5 \\times 10^{-3}$ to $2 \\times 10^{-1}$ in $10^{10}\\,\\mathrm{M_\\odot}$ haloes and from $2 \\times 10^{-2}$ to $4 \\times 10^{-1}$ in $10^{11}\\,\\mathrm{M_\\odot}$ haloes as the redshift increases from $z=0$ to $10$. The accompanying feedback disrupts the gas discs of the most compact systems, while prominent stellar spiral arms emerge. Self-gravitationally bound star clusters form only in compact discs. We find no bound star clusters at $z \\leq 2$ in $10^{10}\\,\\mathrm{M_\\odot}$ haloes, whereas the bound cluster mass fraction reaches $\\approx 40$ per cent at $z \\geq 8$ and $\\approx 70$ per cent in the most compact $10^{11}\\,\\mathrm{M_\\odot}$ halo. These fractions are broadly consistent with those inferred for high-$z$ clumpy galaxies observed by the James Webb Space Telescope.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.07635",
  "author_total": 2,
  "authors": [
    {
      "name": "Shu Horie"
    },
    {
      "name": "Hidenobu Yajima"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fe8vd7wm9e04n.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.07635",
  "fulltext_url": null,
  "id": "fe8vd7wm9e04n",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.07635",
  "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": "W7212045570",
  "pdf_url": "https://arxiv.org/pdf/2609.07635",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-07",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/fe8vd7wm9e04n.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:48Z",
      "native_id": "2609.07635",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.07635"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "A new clump-based star formation model for galaxy simulations: implications for high-redshift compact star clusters",
  "title_text": "A new clump-based star formation model for galaxy simulations: implications for high-redshift compact star clusters",
  "type": "preprint",
  "updated_at": "2026-10-30T12:19:48Z",
  "url": "https://research.draconitic.com/paper/fe8vd7wm9e04n",
  "venue": "arXiv",
  "versions": []
}