{
  "abstract": "We present simulations of the microwave sky at 2.5 arcsecond resolution over 100 square degrees, generated from existing full-sky, lower-resolution simulations, and use them to demonstrate extragalactic foreground removal for a CMB-HD survey. Our cleaning method detects and removes the cosmic infrared background and radio galaxies, yielding source catalogs that are 95% complete down to flux limits of 0.008 and 0.04 mJy at 90 and 148 GHz, respectively. It also identifies and removes galaxy clusters via the thermal Sunyaev-Zel'dovich effect, producing a cluster sample that is nearly complete above $M_{500c} = 5 \\times 10^{13} M_\\odot$. After cleaning, the residual foreground-plus-noise power spectrum of the coadded 90 and 148 GHz temperature map is 50% higher than previous idealized estimates, increasing cosmological parameter uncertainties for an 11-parameter $Λ$CDM + $N_\\mathrm{eff}$ + $\\sum m_ν$ + $T_\\mathrm{AGN}$ + $A_\\mathrm{kSZ}$ + $n_\\mathrm{kSZ}$ model by less than 7%. The small impact on cosmological parameters reflects the strong constraining power of CMB polarization, the temperature-polarization cross spectra, and CMB lensing spectra reconstructed from polarization-only estimators, all of which are minimally affected by extragalactic foregrounds. In particular, the survey remains a sensitive probe of light thermal relic particles, achieving $σ(N_\\mathrm{eff}) = 0.0154$, which can exclude any new species ($ΔN_\\mathrm{eff} \\ge 0.027$) with at least 90% confidence. Our simulation and foreground-removal codes are publicly available and should aid the development of analysis pipelines for ultradeep, ultrahigh-resolution microwave surveys.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.16128",
  "author_total": 5,
  "authors": [
    {
      "name": "Amanda MacInnis"
    },
    {
      "name": "Joshua Ange"
    },
    {
      "name": "Neelima Sehgal"
    },
    {
      "name": "Joshua A. Kable"
    },
    {
      "name": "Isabelle Blackstad"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/ac75ezzcx2g79.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.16128",
  "fulltext_url": null,
  "id": "ac75ezzcx2g79",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.16128",
  "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.CO"
    ],
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "openalex",
      "3103|Cosmology and Gravitation Theories"
    ]
  ],
  "openalex": "W7213407830",
  "pdf_url": "https://arxiv.org/pdf/2609.16128",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-14",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/ac75ezzcx2g79.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:41Z",
      "native_id": "2609.16128",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.16128"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "physics",
      "origin": "arxiv:hep-ph",
      "subfield": "high-energy"
    }
  ],
  "title": "CMB-HD Foregrounds: Simulations, Source Detection, and Foreground Removal",
  "title_text": "CMB-HD Foregrounds: Simulations, Source Detection, and Foreground Removal",
  "type": "preprint",
  "updated_at": "2026-10-30T12:21:41Z",
  "url": "https://research.draconitic.com/paper/ac75ezzcx2g79",
  "venue": "arXiv",
  "versions": []
}