{
  "annotation_id": "8d2cc21a-32d2-4254-8378-93a0f6025f4b",
  "date_created": "2026-03-02T18:02:34.314000Z",
  "date_modified": "2026-03-02T18:02:34.314000Z",
  "file_hash": "afbaa274063682f7444e63849fed8fd10dce83ba35abcec9f3729584d211ef9a",
  "private": false,
  "record": {
    "abstract": "The one-dimensional Klein-Gordon equation is investigated with the most\ngeneral Lorentz structure for the external potentials. The analysis of the\nscattering of particles in a step potential with an arbitrary mixing of vector\nand scalar couplings reveals that the scalar coupling contributes for\nincreasing the threshold energy for the particle-antiparticle pair production.\nFurthermore, it is shown that the pair production is only feasible whether the\nvector coupling exceeds the scalar one. An apparent paradox concerning the\nlocalization of a particle in an arbitrarily small region of space, due to the\npresence of the scalar coupling, is solved by introducing the concept of\neffective Compton wavelength.",
    "arxiv_id": "quant-ph/0702143",
    "authors": [
      "Tatiana R. Cardoso",
      "Antonio S. de Castro"
    ],
    "categories": [
      "quant-ph"
    ],
    "journal_ref": "Rev.Bras.Ens.Fis.29:203-208,2007",
    "title": "On the Threshold for the Pair Production and Localization of Spinless   Particles",
    "url": "https://arxiv.org/abs/quant-ph/0702143"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "b348a84d-4305-4329-bbca-630485791ddf",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}