{
  "abstract": "The UV luminosity function (UVLF) encodes key information about galaxy formation. The slowly evolving bright-end UVLFs at $z\\gtrsim10$ have made UV variability from bursty star formation a promising explanation, but the impact of such variability need not be restricted to the bright end. Motivated by ultra-deep measurements of the $z\\simeq7$ UVLF, we investigate whether UV variability can provide a unified interpretation of the low-mass star formation efficiency (SFE) at $z\\simeq7$ and the abundance of UV-bright galaxies at $z\\gtrsim12$. Using abundance matching, we show that a steep faint-end UVLF at $z\\simeq7$ admits a range of interpretations. For modest, mass-independent UV variability, the inferred median SFE starts flattening below $M_{\\rm h} \\sim10^{10.5} M_{\\odot}$. If UV variability instead grows with decreasing halo mass---a possibility motivated by simulations and observations---the inferred median SFE is steeper and lower by a factor of about three at $\\sim10^9 M_{\\odot}$, consistent with stronger feedback suppression in low-mass halos. Calibrated to the common target $z\\simeq7$ UVLF, these two scenarios diverge strongly when extrapolated to $12\\lesssim z\\lesssim17$ under redshift-independent UV variability and SFE prescriptions. Strongly mass-dependent $M_\\mathrm{UV}$ scatter links the steep $z\\simeq7$ faint-end slope and high $z\\gtrsim12$ bright-end abundance as dual signatures of burstiness in similarly low-mass halos. Stronger variability makes bright galaxies contribute a larger fraction of the UV luminosity density, whereas weaker variability favors faint sources, despite their similar predicted reionization histories. At fixed $M_\\mathrm{UV}$, UV variability broadens the halo mass distribution and lowers the clustering bias, which provides a useful diagnostic of burstiness for JWST and Roman.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.22431",
  "author_total": 4,
  "authors": [
    {
      "name": "Guochao Sun"
    },
    {
      "name": "Claude-André Faucher-Giguère"
    },
    {
      "name": "Steven R. Furlanetto"
    },
    {
      "name": "Adam Lidz"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/34kphrr6tt772.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.22431",
  "fulltext_url": null,
  "id": "34kphrr6tt772",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.22431",
  "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": null,
  "pdf_url": "https://arxiv.org/pdf/2609.22431",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-18",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/34kphrr6tt772.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:19Z",
      "native_id": "2609.22431",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.22431"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "Dual Signatures of Bursty Star Formation in High-Redshift UV Luminosity Functions",
  "title_text": "Dual Signatures of Bursty Star Formation in High-Redshift UV Luminosity Functions",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:19Z",
  "url": "https://research.draconitic.com/paper/34kphrr6tt772",
  "venue": "arXiv",
  "versions": []
}