{
  "annotation_id": "f03f29af-2fe4-4286-a349-e47bf6353f1a",
  "date_created": "2026-03-02T18:00:00.540000Z",
  "date_modified": "2026-03-02T18:00:00.540000Z",
  "file_hash": "9e218008b654986fda27f1b50507fc36afa5a030d789b575e35188140711c792",
  "private": false,
  "record": {
    "abstract": "The onset of intruder ground states in Na isotopes is investigated by\ncomparing experimental data and shell-model calculations. This onset is one of\nthe consequences of the disappearance of the N=20 magic structure, and the Na\nisotopes are shown to play a special role in clarifying the change of this\nmagic structure. Both the electromagnetic moments and the energy levels clearly\nindicate an onset of ground state intruder configurations at neutron number\nN=19 already, which arises only with a narrow N=20 shell gap in Na isotopes\nresulting from the spin-isospin dependence of the nucleon-nucleon interaction\n(as compared to a wider gap in stable nuclei like 40Ca). It is shown why the\nprevious report based on the mass led to a wrong conclusion.",
    "arxiv_id": "nucl-th/0407082",
    "authors": [
      "Yutaka Utsuno",
      "Takaharu Otsuka",
      "Thomas Glasmacher",
      "Takahiro Mizusaki",
      "Michio Honma"
    ],
    "categories": [
      "nucl-th"
    ],
    "doi": "10.1103/PhysRevC.70.044307",
    "journal_ref": "Phys.Rev. C70 (2004) 044307",
    "title": "Onset of intruder ground state in exotic Na isotopes and evolution of   the N=20 shell gap",
    "url": "https://arxiv.org/abs/nucl-th/0407082"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "526dee42-14ee-49cb-a4f3-e8fbec906440",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}