{
  "abstract": "We use Voyager 2 measurements of plasma parameters and magnetic field to constrain energetic neutral atom (ENA) fluxes observed by Interstellar Boundary Explorer (IBEX). Unlike previous ENA models, our calculation does not directly use the ion distributions from global heliosphere simulations. Instead, we model the pickup ion velocity distributions based on previous kinetic simulations of the termination shock and the expected energy-dependent charge-exchange rate in the heliosheath based on Voyager 2 observations. The effects of flow compression on the ion distributions are quantified. Motivated by the recent finding that the newborn pickup ions in the heliosheath may maintain anisotropy, we consider both the isotropic limit and the anisotropic limit with no pitch-angle scattering. We also use hybrid kinetic simulations with continued pickup ion injection to investigate the evolution of the anisotropy due to self-generated kinetic instabilities. In all cases, the modeled ENA fluxes significantly underpredict the IBEX observations, especially in low energies (between about 0.05 and 1 keV), confirming previous global-simulation-based studies. We explore several possible explanations for this discrepancy, such as magnetic reconnection, uncertainties in the heliosheath flow speed, and additional ENA sources in the interstellar medium.",
  "abstract_shown": true,
  "affiliations": [
    "Boston University",
    "University of Arizona",
    "University of Maryland"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 6,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Senbei Du",
      "orcid": "0000-0003-1134-3909"
    },
    {
      "affs": [
        0
      ],
      "name": "Merav Opher",
      "orcid": "0000-0002-8767-8273"
    },
    {
      "affs": [
        0
      ],
      "name": "Marc Kornbleuth",
      "orcid": "0000-0002-3479-1766"
    },
    {
      "affs": [
        0
      ],
      "name": "Ethan Schuyler Bair",
      "orcid": "0000-0003-0610-1382"
    },
    {
      "affs": [
        1
      ],
      "name": "Joe Giacalone",
      "orcid": "0000-0002-0850-4233"
    },
    {
      "affs": [
        2
      ],
      "name": "Jeewoo Park",
      "orcid": "0000-0002-8989-4631"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2vkakm5trzye7.bib",
  "cited_by": 0,
  "doi": "10.3847/1538-4365/aea206",
  "fulltext_url": null,
  "id": "2vkakm5trzye7",
  "issns": [
    "0067-0049",
    "1538-4365"
  ],
  "landing_url": "https://iopscience.iop.org/article/10.3847/1538-4365/aea206",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "3103|Solar and Space Plasma Dynamics"
    ]
  ],
  "openalex": "W7220706664",
  "pdf_url": "https://iopscience.iop.org/article/10.3847/1538-4365/aea206/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-07",
  "publisher": "American Astronomical Society",
  "ris": "https://research.draconitic.com/paper/2vkakm5trzye7.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:15Z",
      "native_id": "10.3847/1538-4365/aea206",
      "source": "crossref",
      "url": "https://iopscience.iop.org/article/10.3847/1538-4365/aea206"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "openalex:3103|Solar and Space Plasma Dynamics",
      "subfield": "stellar"
    }
  ],
  "title": "The Velocity Distribution of Heliosheath-created Pickup Ions along Voyager 2’s Trajectory and Energetic Neutral Atom Fluxes",
  "title_text": "The Velocity Distribution of Heliosheath-created Pickup Ions along Voyager 2’s Trajectory and Energetic Neutral Atom Fluxes",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:18:15Z",
  "url": "https://research.draconitic.com/paper/2vkakm5trzye7",
  "venue": "The Astrophysical Journal Supplement Series",
  "versions": []
}