{
  "annotation_id": "c8e5522f-7525-4b9f-800c-a8e4e9085824",
  "date_created": "2026-03-02T18:00:50.371000Z",
  "date_modified": "2026-03-02T18:00:50.371000Z",
  "file_hash": "c2fef54a6651fa9110b0b751aec636b10d98d356cbd4d2cc3f9b6091ff4cfb5e",
  "private": false,
  "record": {
    "abstract": "We have measured the frequency splitting between the $(2S, F=1/2)$ and $(2S,\nF=3/2)$ hyperfine sublevels in atomic deuterium by an optical differential\nmethod based on two-photon Doppler-free spectroscopy on a cold atomic beam. The\nresult $f_{\\rm HFS}^{(D)}(2S)= 40 924 454(7)$ Hz is the most precise value for\nthis interval to date. In comparison to the previous radio-frequency\nmeasurement we have improved the accuracy by the factor of three.\n  The specific combination of hyperfine frequency intervals for metastable- and\nground states in deuterium atom $D_{21}=8f_{\\rm HFS}^{(D)}(2S)-f_{\\rm\nHFS}^{(D)}(1S)$ derived from our measurement is in a good agreement with\n$D_{21}$ calculated from quantum-electrodynamics theory.",
    "arxiv_id": "physics/0405058",
    "authors": [
      "N. Kolachevsky",
      "P. Fendel",
      "S. G. Karshenboim",
      "T. W. H\u00e4nsch"
    ],
    "categories": [
      "physics.atom-ph"
    ],
    "doi": "10.1103/PhysRevA.70.062503",
    "journal_ref": "Phys. Rev. A 70, 062503 (2004)",
    "title": "2S hyperfine structure of atomic deuterium",
    "url": "https://arxiv.org/abs/physics/0405058"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "9bb7e182-cf70-4caa-8bfb-5146a593902b",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}