{
  "abstract": "Photochemical hazes play an important role in shaping the spectra and radiative balance of N ₂ -dominated planetary atmospheres. We present newly acquired Fourier transform infrared (FTIR) and retrieved optical constants ( N = n + ik ) of laboratory-generated haze analogs from N ₂ /CH ₄ and N ₂ /CH ₄ /CO gas mixtures under plasma discharge conditions. The retrievals use particle densities newly measured for the CH ₄ series and previously published particle densities for the CO series. The experiments systematically explored CH ₄ concentrations from 0.5% to 10% and CO concentrations from 0% to 5% with fixed 5% CH ₄ . Using measured particle densities together with the Beer–Lambert law and the subtractive Kramers–Kronig (SKK) relation, we derived optical constants over the 350–25,000 cm ⁻¹ (0.4–28.6 μ m) spectral range, with the 0.4–25 μ m results presented in the main text. The infrared spectra reveal prominent absorption features associated with hydrocarbon-, nitrogen-, and oxygen-bearing functional groups. Increasing CH ₄ abundance enhances aliphatic hydrocarbon features and corresponds to decreasing particle density, whereas increasing CO abundance promotes oxygen incorporation, broader mid-infrared absorptions, and higher particle density. The derived k spectra exhibit strong absorptions near ∼3 μ m, ∼4.6 μ m, and ∼6–10 μ m, while the real refractive index n generally ranges from ∼1.2 to 1.7. The controlled CH ₄ and CO series establish composition-dependent variations in haze optical properties. A benchmark comparison among Titan-, Pluto-, and Triton-like haze analogs then uses these experimentally identified trends to interpret the optical differences among N ₂ -dominated planetary haze compositions. The density and optical constants provide laboratory constraints for atmospheric radiative transfer models and for interpreting planetary and exoplanetary spectra from spacecraft and telescopes.",
  "abstract_shown": true,
  "affiliations": [
    "University of Science and Technology of China",
    "Johns Hopkins University",
    "Space Telescope Science Institute"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Zhengbo Yang",
      "orcid": "0009-0000-7676-171X"
    },
    {
      "affs": [
        0
      ],
      "name": "Chao He",
      "orcid": "0000-0002-6694-0965"
    },
    {
      "affs": [
        0
      ],
      "name": "Haixin Li",
      "orcid": "0009-0009-2660-1764"
    },
    {
      "affs": [
        0
      ],
      "name": "Sai Wang",
      "orcid": "0009-0001-9044-7927"
    },
    {
      "affs": [
        0
      ],
      "name": "Xiao’ou Luo",
      "orcid": "0009-0001-1702-5242"
    },
    {
      "affs": [
        0
      ],
      "name": "Yu Liu",
      "orcid": "0000-0002-6085-9365"
    },
    {
      "affs": [
        1,
        2
      ],
      "name": "Sarah M. Hörst",
      "orcid": "0000-0003-4596-0702"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bxepfn4p4nany.bib",
  "cited_by": 0,
  "doi": "10.3847/1538-4365/aeaffe",
  "fulltext_url": null,
  "id": "bxepfn4p4nany",
  "issns": [
    "0067-0049",
    "1538-4365"
  ],
  "landing_url": "https://iopscience.iop.org/article/10.3847/1538-4365/aeaffe",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [],
  "openalex": null,
  "pdf_url": "https://iopscience.iop.org/article/10.3847/1538-4365/aeaffe/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-04",
  "publisher": "American Astronomical Society",
  "ris": "https://research.draconitic.com/paper/bxepfn4p4nany.ris",
  "sources": [
    {
      "first_seen": "2026-11-04T12:20:55Z",
      "native_id": "10.3847/1538-4365/aeaffe",
      "source": "crossref",
      "url": "https://iopscience.iop.org/article/10.3847/1538-4365/aeaffe"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "journal-openalex:3103|Stellar, planetary, and galactic studies",
      "subfield": "stellar"
    }
  ],
  "title": "Optical Constants of Photochemical Haze Analogs in N ₂ –CH ₄ –CO Atmospheres from 0.4 to 28.6 μ m",
  "title_text": "Optical Constants of Photochemical Haze Analogs in N ₂ –CH ₄ –CO Atmospheres from 0.4 to 28.6 μ m",
  "type": "peer-reviewed",
  "updated_at": "2026-11-06T00:21:01Z",
  "url": "https://research.draconitic.com/paper/bxepfn4p4nany",
  "venue": "The Astrophysical Journal Supplement Series",
  "versions": []
}