{
  "annotation_id": "1a6c3e85-3c25-4f58-a657-96d3ec6190d9",
  "date_created": "2026-03-02T18:00:39.726000Z",
  "date_modified": "2026-03-02T18:00:39.726000Z",
  "file_hash": "74b90324ccbd26b326e69b50071ad3120e2ec817376676cc75b0c1e3c18da9aa",
  "private": false,
  "record": {
    "abstract": "We use a diode laser locked to a Rb transition as the frequency reference\nalong with a scanning Michelson interferometer to make precise measurements on\nthe $D_1$ and $D_2$ lines of potassium. The Rb reference frequency is known\nwith sub-MHz accuracy. We obtain the following values for the energy levels: 12\n985.169 60(13)(15) cm$^{-1}$ for the $4P_{1/2}$ state ($D_1$ line); 13 042.875\n95(14)(15) cm$^{-1}$ for the $4P_{3/2}$ state ($D_2$ line); and 57.706\n35(19)(15) cm$^{-1}$ for the $4P_{3/2}-4P_{1/2}$ fine-structure interval. The\nleading source of systematic error cancels in the determination of the\ninterval. The errors represent about an order of magnitude improvement over\ntabulated values.",
    "arxiv_id": "physics/0204063",
    "authors": [
      "Ayan Banerjee",
      "Dipankar Das",
      "Vasant Natarajan"
    ],
    "categories": [
      "physics.atom-ph",
      "physics.optics"
    ],
    "doi": "10.1364/JOSAB.21.000079",
    "journal_ref": "J. Opt. Soc. Am. B, vol. 21 (1), pp. 79-82 (2004)",
    "title": "Precise frequency measurements of the D-lines and fine-structure   interval in K",
    "url": "https://arxiv.org/abs/physics/0204063"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "96c075a6-6291-483a-a41d-4531fe50f06a",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}