{
  "abstract": "Aerosols - solid or liquid particles suspended in air - are an effective means of dispersing chemical warfare agents and toxic pharmaceuticals, posing acute risks to public safety and security. Exposure to aerosol particulate matter in the environment and in industrial settings has also been linked to respiratory and cardiovascular disease. In both cases, rapid chemical identification is key to generating early warnings and attributing sources. Established methods chemically identify aerosols only after extracting a sample, while standoff techniques such as lidar classify aerosols only into broad categories. Chemical identification at a distance is hindered by aerosol extinction signatures that are weak, spectrally broad, and obscured by far stronger absorption from ambient gases. Here, we demonstrate time-resolved, standoff chemical differentiation of aerosols with dual-comb spectroscopy and machine learning identification algorithms. The high spectral resolution of dual-comb spectroscopy allows ambient gas absorption to be removed, and the algorithms identify chemicals without knowledge of aerosol size and morphology. We demonstrate identification of aerosolized benzyl fentanyl (a fentanyl simulant) in mixtures with other aerosols in a standoff measurement through ambient H2O, CO2, and CH4. Despite the aerosol producing only subtle, <1% changes in the extinction spectrum across hundreds of wavenumbers, we find the limit of identification to be an order of magnitude below lethal concentrations for a 1 m aerosol cloud. This technique provides a new paradigm for performing rapid chemical speciation of aerosols using their infrared absorption signatures without extractive sampling. Together with advances in chip-based mid-infrared dual-comb spectrometry, we anticipate this technique will enable real-time networks for standoff detection of aerosol emissions and aerosolized chemical threats.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2611.09999",
  "author_total": 24,
  "authors": [
    {
      "name": "Garrett C. Mathews"
    },
    {
      "name": "Alyssa Lalko"
    },
    {
      "name": "Anna C. Ziola"
    },
    {
      "name": "Masayuki Takeuchi"
    },
    {
      "name": "Leo C. Bloxham"
    },
    {
      "name": "Douglas A. Day"
    },
    {
      "name": "Anne V. Handschy"
    },
    {
      "name": "Amanda Makowiecki"
    },
    {
      "name": "Kevin Williamson"
    },
    {
      "name": "Nazanin Hoghooghi"
    },
    {
      "name": "Scott Egbert"
    },
    {
      "name": "Peter Chang"
    },
    {
      "name": "Tsung-Han Wu"
    },
    {
      "name": "Anthony Harness"
    },
    {
      "name": "Robert Wright"
    },
    {
      "name": "Jiang Li"
    },
    {
      "name": "Tin Komljenovic"
    },
    {
      "name": "John Bowers"
    },
    {
      "name": "Satoshi Takahama"
    },
    {
      "name": "Daven Henze"
    },
    {
      "name": "Kerry Vahala"
    },
    {
      "name": "Scott A. Diddams"
    },
    {
      "name": "Jose L. Jimenez"
    },
    {
      "name": "Gregory B. Rieker"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6szc16s0nr1f2.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2611.09999",
  "fulltext_url": null,
  "id": "6szc16s0nr1f2",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2611.09999",
  "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",
      "physics.chem-ph"
    ],
    [
      "arxiv",
      "physics.optics"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2611.09999",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-03",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/6szc16s0nr1f2.ris",
  "sources": [
    {
      "first_seen": "2026-11-10T06:21:23Z",
      "native_id": "2611.09999",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2611.09999"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "arxiv:physics.chem-ph",
      "subfield": "physical"
    },
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    }
  ],
  "title": "Standoff chemical identification of harmful aerosols",
  "title_text": "Standoff chemical identification of harmful aerosols",
  "type": "preprint",
  "updated_at": "2026-11-10T06:21:23Z",
  "url": "https://research.draconitic.com/paper/6szc16s0nr1f2",
  "venue": "arXiv",
  "versions": []
}