{
  "annotation_id": "f1348584-861a-4d66-9d12-a583fcebf226",
  "date_created": "2026-03-02T18:00:36.281000Z",
  "date_modified": "2026-03-02T18:00:36.281000Z",
  "file_hash": "57735d37076aea2f308c3712eac2ae93ed2a050c0a08058b030b509dc9f1fb61",
  "private": false,
  "record": {
    "abstract": "Ultracold atoms at temperatures close to the recoil limit have been achieved\nby extending Doppler cooling to forbidden transitions. A cloud of ^40Ca atoms\nhas been cooled and trapped to a temperature as low as 6 \\mu K by operating a\nmagneto-optical trap on the spin-forbidden intercombination transition.\nQuenching the long-lived excited state with an additional laser enhanced the\nscattering rate by a factor of 15, while a high selectivity in velocity was\npreserved. With this method more than 10% of pre-cooled atoms from a standard\nmagneto-optical trap have been transferred to the ultracold trap. Monte-Carlo\nsimulations of the cooling process are in good agreement with the experiments.",
    "arxiv_id": "physics/0105069",
    "authors": [
      "T. Binnewies",
      "G. Wilpers",
      "U. Sterr",
      "F. Riehle",
      "J. Helmcke",
      "T. E. Mehlst\u00e4ubler",
      "E. M. Rasel",
      "W. Ertmer"
    ],
    "categories": [
      "physics.atom-ph"
    ],
    "doi": "10.1103/PhysRevLett.87.123002",
    "journal_ref": "Phys. Rev. Lett. 87, 123002 (2001)",
    "title": "Doppler cooling and trapping on forbidden transitions",
    "url": "https://arxiv.org/abs/physics/0105069"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "517d2b56-ae9f-40e2-92af-bd046daa006f",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}