{
  "abstract": "JWST/NIRCam has recovered the stellar counterparts of many ALMA-detected, formerly HST-dark galaxies, yet ALMA has started identifying dusty star-forming galaxies (DSFGs) at $z>6$ that remain extremely faint or undetected even with NIRCam. These \"NIRCam-dark\" DSFGs may trace a missing rapid-growth phase connecting UV-luminous galaxies at $z>10$ to massive quiescent galaxies at $z\\gtrsim4$. So far, the small, heterogeneously selected NIRCam-dark sample is insufficient to determine their abundance or role in the evolution of massive galaxies. We show that a blind 1.3-mm continuum survey with ALMA2040 can provide the first high-significance census of this elusive NIRCam-dark DSFG population across $z\\simeq 6 - 9$. We conduct sensitivity and survey-speed calculations requiring a $10σ$ detection of a NIRCam-dark DSFG with a dust-obscured star-formation rate of $60\\,M_\\odot\\,{\\rm yr}^{-1}$ at $z = 8$. At a like-for-like 7.5-GHz normalization, ALMA2040 will reach the required 1.3-mm RMS of $21\\,μ$Jy beam$^{-1}$ about 90 times faster than current ALMA. With 100 hr on-source, ALMA2040 can cover an area of $\\sim0.5$ deg$^2$ and detect $\\langle N \\rangle\\sim16$ NIRCam-dark DSFGs over $7.5<z<9$, assuming a fiducial number density $n=3\\times10^{-6}$ cMpc$^{-3}$. Dividing the survey among independent fields with deep JWST coverage would mitigate cosmic variance and enable immediate NIRCam, MIRI, and spectroscopic characterization of their environments. The $\\geq512$-GHz instantaneous bandwidth expected for ALMA2040 will also detect [C II] line at a wide redshift range, supplementing the continuum discovery with redshift confirmation. Such a survey will test whether NIRCam-dark DSFGs trace a missing rapid-growth phase between the earliest UV-luminous galaxies at $z>10$ and the rapid emergence of massive quiescent systems at $z\\gtrsim 4$.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.20727",
  "author_total": 24,
  "authors": [
    {
      "name": "Fengwu Sun"
    },
    {
      "name": "Belén Alcalde Pampliega"
    },
    {
      "name": "Hiddo Algera"
    },
    {
      "name": "Manuel Aravena"
    },
    {
      "name": "Tom Bakx"
    },
    {
      "name": "Karina I. Caputi"
    },
    {
      "name": "Pierre Cox"
    },
    {
      "name": "Elisabete da Cunha"
    },
    {
      "name": "Andreas Faisst"
    },
    {
      "name": "Yoshinobu Fudamoto"
    },
    {
      "name": "Carlotta Gruppioni"
    },
    {
      "name": "Mahmoud Hamed"
    },
    {
      "name": "Jacqueline Hodge"
    },
    {
      "name": "Patrick S. Kamieneski"
    },
    {
      "name": "Adarsh Kumar"
    },
    {
      "name": "Ivanna Langan"
    },
    {
      "name": "Andrea Lapi"
    },
    {
      "name": "Umberto Maio"
    },
    {
      "name": "Chiara Mazzucchelli"
    },
    {
      "name": "Dieu D. Nguyen"
    },
    {
      "name": "Mamta Pandey-Pommier"
    },
    {
      "name": "Dominik A. Riechers"
    },
    {
      "name": "Irene Shivaei"
    },
    {
      "name": "Sabine Thater"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/07xw0zdpp4sza.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.20727",
  "fulltext_url": null,
  "id": "07xw0zdpp4sza",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.20727",
  "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"
    ],
    [
      "arxiv",
      "astro-ph.IM"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2610.20727",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-14",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/07xw0zdpp4sza.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:50Z",
      "native_id": "2610.20727",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.20727"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.IM",
      "subfield": "instrumentation-methods"
    }
  ],
  "title": "Has JWST Seen Everything? Hunting for \"NIRCam-dark\" Dusty Star-Forming Galaxies at $z \\simeq 6 - 9$ with ALMA2040",
  "title_text": "Has JWST Seen Everything? Hunting for \"NIRCam-dark\" Dusty Star-Forming Galaxies at z ≃ 6 − 9 with ALMA2040",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:50Z",
  "url": "https://research.draconitic.com/paper/07xw0zdpp4sza",
  "venue": "arXiv",
  "versions": []
}