{
  "annotation_id": "254b5ec3-ada4-4246-94c5-d9a38266e71f",
  "date_created": "2026-03-02T18:00:01.187000Z",
  "date_modified": "2026-03-02T18:00:01.187000Z",
  "file_hash": "4c7639c94efc5d0fede03e876d883fe9d48320291679a7052a90ad32834f5ea3",
  "private": false,
  "record": {
    "abstract": "It is argued that in the antiproton-proton annihilation into two mesons $\\bar\npp\\longrightarrow m_1 m_2$, the origin of different restrictive angular\nmomentum selection rules commonly obtained for planar annihilation diagrams\n$A2$ and for non-planar rearrangement diagrams $R2$ lies in the omission of\nmomentum transfer between an annihilated antiquark-quark pair and a remaining\nquark or antiquark. If it is included, there is no reason for dismissing one\ntype of diagram in favor of another one. Some considerations in the large $N_c$\nlimit of QCD equally shed light on the planar and non-planar contributions to\nthe total $\\bar NN\\to m_1 m_2$ annihilation amplitude.",
    "arxiv_id": "nucl-th/0407109",
    "authors": [
      "B. El-Bennich"
    ],
    "categories": [
      "nucl-th",
      "hep-ph"
    ],
    "doi": "10.1103/PhysRevC.72.067001",
    "journal_ref": "Phys.Rev. C72 (2005) 067001",
    "title": "Planar versus non-planar anti-NN annihilation into mesons in the light   of anti-qq operators and the 1/Nc expansion",
    "url": "https://arxiv.org/abs/nucl-th/0407109"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "c5d38ad0-0d27-49b0-b26a-6f02acdbb1ac",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}