{
  "annotation_id": "2a7ee408-7d0d-45b2-8978-4ff6cb239e56",
  "date_created": "2026-03-02T18:00:17.787000Z",
  "date_modified": "2026-03-02T18:00:17.787000Z",
  "file_hash": "67163a821efcbd90ca0b78ddfc93b19fcab2fc6ece75e995efc1b5b7fe3cfc0f",
  "private": false,
  "record": {
    "abstract": "The possibility of pion--pair formation in a hot pion gas, based on the\nbosonic gap equation, is pointed out and discussed in detail. The critical\ntemperature for condensation of pion pairs (Evans--Rashid transition) is\ndetermined as a function of the pion density. As for fermions, this phase\ntransition is signaled by the appearance of a pole in the two--particle\npropagator. In bose systems there exists a second, lower critical temperature,\nassociated with the appearance of the single--particle condensate. Between the\ntwo critical temperatures the pion dispersion relation changes from the usual\nquasiparticle dispersion to a Bogoliubov--like dispersion relation at low\nmomenta. This generalizes the non-relativistic result for an attractive bose\ngas by Evans et al. Possible consequences for the inclusive pion spectra\nmeasured in heavy--ion collisions at ultra--relativistic energies are\ndiscussed.",
    "arxiv_id": "nucl-th/9609036",
    "authors": [
      "T. Alm",
      "G. Chanfray",
      "P. Schuck",
      "G. Welke"
    ],
    "categories": [
      "nucl-th",
      "atom-ph",
      "hep-ph"
    ],
    "doi": "10.1016/S0375-9474(96)00409-5",
    "journal_ref": "Nucl.Phys. A612 (1997) 472-492",
    "title": "Pion-pair formation and the pion dispersion relation in a hot pion gas",
    "url": "https://arxiv.org/abs/nucl-th/9609036"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "fd2f024c-cf01-4677-abcb-186eb6a3b41e",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}