{
  "annotation_id": "d65b335f-1f27-4383-8a68-d9b38496ac32",
  "date_created": "2026-03-02T18:00:14.496000Z",
  "date_modified": "2026-03-02T18:00:14.496000Z",
  "file_hash": "d3ee44425944dba993adb25b2e629321ecf4a9dc3b6b1cbb79cb3be5ba26f469",
  "private": false,
  "record": {
    "abstract": "The cross section for the reaction $dd\\rightarrow \\,^4\\!H\\!e\\,\\eta$ close to\nthreshold is estimated in a two-step model, similar to that which successfully\ndescribes near-threshold $pd\\rightarrow \\,^3\\!H\\!e\\,\\eta$ production. A\n$\\pi$-meson, created in a $dp\\rightarrow \\,^3\\!H\\!e\\,\\pi^o$ process on one\nnucleon in the target deuteron, is converted into an $\\eta$-meson by a\nsecondary $\\pi^o n \\to n\\,\\eta$ reaction on the other nucleon. The kinematics\nare such that both processes are nearly physical so that only small Fermi\nmomenta are required. The predictions of the model are in good agreement with\nrecent Saclay experimental data.\n  An analogous model, when applied to the near-threshold\n$n\\,^3\\!H\\!e\\rightarrow \\,^4\\!H\\!e\\,\\eta$ reaction, predicts a cross section of\na rather similar size, but experimental difficulties render this a doubtful\nmeans of studying the $\\eta\\, ^4\\!H\\!e$ interaction.",
    "arxiv_id": "nucl-th/9510004",
    "authors": [
      "G. Faeldt",
      "C. Wilkin"
    ],
    "categories": [
      "nucl-th"
    ],
    "doi": "10.1016/0375-9474(95)00422-X",
    "journal_ref": "Nucl.Phys. A596 (1996) 488-502",
    "title": "The dd -\u003e 4He eta Reaction Near Threshold",
    "url": "https://arxiv.org/abs/nucl-th/9510004"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "95d2a3cf-55b8-4689-9174-d8885eb5fc4d",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}