{
  "annotation_id": "2b4a39b5-382b-4652-94ee-331f73613e21",
  "date_created": "2026-03-02T18:00:46.921000Z",
  "date_modified": "2026-03-02T18:00:46.921000Z",
  "file_hash": "f30b1ecc857ed7e631d9e5b39a65037824ee30f3c0a0423e1066a76fe777c02d",
  "private": false,
  "record": {
    "abstract": "The non-resonant two-photon ionization of hydrogen-like ions is studied in\nsecond-order perturbation theory, based on the Dirac equation. To carry out the\nsummation over the complete Coulomb spectrum, a Green function approach has\nbeen applied to the computation of the ionization cross sections. Exact\nsecond-order relativistic cross sections are compared with data as obtained\nfrom a relativistic long-wavelength approximation as well as from the scaling\nof non-relativistic results. For high-Z ions, the relativistic wavefunction\ncontraction may lower the two-photon ionization cross sections by a factor of\ntwo or more, while retardation effects appear less pronounced but still give\nrise to non-negligible contributions.",
    "arxiv_id": "physics/0307114",
    "authors": [
      "Peter Koval",
      "Stephan Fritzsche",
      "Andrey Surzhykov"
    ],
    "categories": [
      "physics.atom-ph"
    ],
    "doi": "10.1088/0953-4075/36/5/307",
    "journal_ref": "P.Koval, S. Fritzsche and A. Surzhikov, J. Phys. B36 (2003)\n  873-878",
    "title": "Relativistic and retardation effects in the two--photon ionization of   hydrogen--like ions",
    "url": "https://arxiv.org/abs/physics/0307114"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "c0d86ad2-e22b-4f97-89c8-cc349f110e92",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}