{
  "abstract": "The Outer Space Treaty bans nuclear weapons from orbit but lacks a dedicated means of verifying what a closed spacecraft contains. The orbital environment supplies a natural interrogation field: trapped protons induce neutron emission, allowing passive inspection without an active source. Detection can flag an anomalous object from kilometre standoff, but a count does not determine composition. Here we construct a conventional aluminium spacecraft and a uranium-bearing object with nearly identical detector-accepted neutron counts, whose reconstructed spectra remain distinct. In the baseline geometry the full spectrum reaches an area under the receiver-operating characteristic of 0.90 after about 70 accepted neutrons. A tungsten configuration matched to the uranium count rate preserves only about 2.2 per cent of the per-neutron spectral separation, raising the requirement to about 3200 neutrons for discrimination and 8200 for 90 per cent power at 5 per cent false attribution against that alternative. Under a published detector-rate benchmark, ten inspectors at 500 m require about one week for discrimination and less than three weeks for controlled attribution. These thresholds define an inspection claim envelope: detection, discrimination and attribution are distinct measurements with distinct range-dwell regimes. The environment supplies the interrogation; proximity determines what may responsibly be claimed.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 1,
  "authors": [
    {
      "name": "Yasser Maghrbi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8x09r0pgqpxxk.bib",
  "cited_by": 0,
  "doi": null,
  "fulltext_url": null,
  "id": "8x09r0pgqpxxk",
  "issns": [],
  "landing_url": "https://hal.science/hal-05713434v2",
  "language": "en",
  "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": [
    [
      "hal",
      "0.phys"
    ],
    [
      "hal",
      "1.phys.nexp"
    ],
    [
      "hal",
      "1.phys.phys"
    ],
    [
      "hal",
      "2.phys.phys.phys-ins-det"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://hal.science/hal-05713434/document",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-21",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/8x09r0pgqpxxk.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:37Z",
      "native_id": "hal-05713434",
      "source": "hal",
      "url": "https://hal.science/hal-05713434v2"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "hal:2.phys.phys.phys-ins-det",
      "subfield": "applied-instrumentation"
    },
    {
      "field": "physics",
      "origin": "hal:1.phys.nexp",
      "subfield": "nuclear"
    }
  ],
  "title": "Identifying hidden nuclear material in orbit from its own neutron spectrum",
  "title_text": "Identifying hidden nuclear material in orbit from its own neutron spectrum",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:37Z",
  "url": "https://research.draconitic.com/paper/8x09r0pgqpxxk",
  "venue": "HAL",
  "versions": []
}