{
  "abstract": "A novel divertor solution is presented for a pre-conceptual design point of the quasi-axisymmetric stellarator power plant, “Helios.” This solution, isomorphic to the poloidal divertor in a tokamak, features a toroidally-continuous n=0, m=2 double null configuration in which the X-points do not poloidally link the plasma. This results in a non-resonant divertor geometry which relies on neither low-order resonances nor a chaotic boundary region and which features parallel connection lengths similar to those in tokamaks. When reconstructed with a finite-build planar coilset, the configuration resembles that of a tokamak with resonant magnetic perturbations (“RMPs”) applied. Field line tracing and simplified analytic models are used to justify the assumption of tokamak-like Scrape-off Layer (“SOL”) transport and access to a high-recycling regime in such a configuration. Due to this, it is also speculated that high neutral compression akin to a tokamak will be achievable in such a configuration. Preliminary target geometries for this configuration are introduced. Even without globally optimized target geometries, peak heat flux remains below engineering limits for a reference case at similar radiated power fraction as achievable in existing machines ( f r a d = 90 % ) for a baseline P f u s = 958 MW scenario and only slightly exceeds engineering limits for a conservative, low wetted area case. Initial results indicating resilience of the X-point to pressure profile changes are shown. Lastly, preliminary feasibility studies of a disconnected double null configuration are explored, potentially enabling an engineering-simplified design with only lower targets.",
  "abstract_shown": true,
  "affiliations": [
    "Thea Energy, Inc., 1 Eastern Road, Ste. 3-04, Kearny, 07032, NJ, USA",
    "Columbia University, New York, NY, 10027, USA",
    "Princeton University, Princeton, NJ, 08544, USA",
    "Stanford University, Stanford, CA, 94305, USA"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 12,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "E.R. Flom",
      "orcid": "0000-0002-9284-9380"
    },
    {
      "affs": [
        0
      ],
      "name": "W.B. Kalb",
      "orcid": "0000-0002-8342-5455"
    },
    {
      "affs": [
        1
      ],
      "name": "Shreyas Seethalla",
      "orcid": "0000-0001-7793-9110"
    },
    {
      "affs": [
        0
      ],
      "name": "C. P. S. Swanson",
      "orcid": "0000-0003-0231-8525"
    },
    {
      "affs": [
        0
      ],
      "name": "Ryan Wu",
      "orcid": "0000-0002-9738-3081"
    },
    {
      "affs": [
        2
      ],
      "name": "M. Avida",
      "orcid": "0009-0005-4883-8093"
    },
    {
      "affs": [
        0
      ],
      "name": "A.H. Doudna Cate",
      "orcid": "0009-0007-9564-7155"
    },
    {
      "affs": [
        0
      ],
      "name": "Daniel W. Dudt",
      "orcid": "0000-0002-4557-3529"
    },
    {
      "affs": [
        0
      ],
      "name": "Thomas Krüger",
      "orcid": "0000-0003-1462-3033"
    },
    {
      "affs": [
        0
      ],
      "name": "Santhosh T. A. Kumar",
      "orcid": "0000-0002-6444-5178"
    },
    {
      "affs": [
        3
      ],
      "name": "N. Maitra",
      "orcid": "0000-0002-6683-0731"
    },
    {
      "affs": [
        0
      ],
      "name": "D. Gates",
      "orcid": "0000-0001-5679-3124"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/92k402swxy78q.bib",
  "cited_by": 7,
  "doi": "10.1016/j.fusengdes.2026.115846",
  "fulltext_url": null,
  "id": "92k402swxy78q",
  "issns": [
    "0920-3796",
    "1873-7196"
  ],
  "landing_url": "https://doi.org/10.1016/j.fusengdes.2026.115846",
  "language": "en",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "3106|Magnetic confinement fusion research"
    ]
  ],
  "openalex": "W7163672904",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-06-05",
  "publisher": "Elsevier BV",
  "ris": "https://research.draconitic.com/paper/92k402swxy78q.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T13:26:43Z",
      "native_id": "W7163672904",
      "source": "openalex",
      "url": "https://doi.org/10.1016/j.fusengdes.2026.115846"
    }
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  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3106|Magnetic confinement fusion research",
      "subfield": "high-energy"
    }
  ],
  "title": "Design and conceptual modeling of a tokamak-like X-point divertor for the Helios quasi-axisymmetric stellarator",
  "title_text": "Design and conceptual modeling of a tokamak-like X-point divertor for the Helios quasi-axisymmetric stellarator",
  "type": "peer-reviewed",
  "updated_at": "2026-11-03T13:20:27Z",
  "url": "https://research.draconitic.com/paper/92k402swxy78q",
  "venue": "Fusion Engineering and Design",
  "versions": []
}