{
  "annotation_id": "86d5a95e-a069-4c18-8d7b-cb586acf5a2d",
  "date_created": "2026-03-02T18:00:07.911000Z",
  "date_modified": "2026-03-02T18:00:07.911000Z",
  "file_hash": "88f44bcc576f3c3d1d0fff4517f7860dfb2b859cf7d7a88c0dedc753e3d30258",
  "private": false,
  "record": {
    "abstract": "Unstable states of the eta meson and the 3He nucleus predicted using the time\ndelay method were found to be in agreement with a recent claim of eta-mesic 3He\nstates made by the TAPS collaboration. Here, we extend this method to a\nspeculative study of the unstable states occurring in the eta-d and eta-4He\nelastic scattering. The T-matrix for eta-4He scattering is evaluated within the\nFinite Rank Approximation (FRA) of few body equations. For the evaluation of\ntime delay in the eta-d case, we use a parameterization of an existing Faddeev\ncalculation and compare the results with those obtained from FRA. With an eta-N\nscattering length, $a_{\\eta N} = (0.42, 0.34)$ fm, we find an eta-d unstable\nbound state around -16 MeV, within the Faddeev calculation. A similar state\nwithin the FRA is found for a low value of $a_{\\eta N}$, namely, $a_{\\eta N} =\n(0.28, 0.19)$ fm. The existence of an eta-4He unstable bound state close to\nthreshold is hinted by $a_{\\eta N} = (0.28, 0.19)$ fm, but is ruled out by\nlarge scattering lengths.",
    "arxiv_id": "nucl-th/0606028",
    "authors": [
      "N. G. Kelkar",
      "K. P. Khemchandani",
      "B. K. Jain"
    ],
    "categories": [
      "nucl-th"
    ],
    "doi": "10.1088/0954-3899/32/8/007",
    "journal_ref": "J.Phys.G32:1157-1170,2006",
    "title": "Small eta-N scattering lengths favour eta-d and eta-alpha states",
    "url": "https://arxiv.org/abs/nucl-th/0606028"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "d0bb69fa-e552-45bf-80e7-d7e5bc9c74f9",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}