{
  "annotation_id": "d49f88a2-48c1-4717-8cce-e90a82f0631d",
  "date_created": "2026-03-02T18:00:35.441000Z",
  "date_modified": "2026-03-02T18:00:35.441000Z",
  "file_hash": "e730758e658a492cc84f2c0b85ce75592cb15ef0aa9b1b598084cc9685bbc825",
  "private": false,
  "record": {
    "abstract": "The LIGO Interferometer Sensing and Control System (ISC) is a large and\nhighly distributed Multiple Input Multiple Output (MIMO) control system that is\nused to control the length and alignment degrees of freedom of the\ninterferometers. The 4 kilometer Fabry-Perot cavity lengths are controlled to\nbetter than 10-13 meters (rms) and the angular degrees of freedom are\ncontrolled to better than 10-8 radians. This paper will describe the real-time\ndigital servo control systems that have been designed, developed and\nimplemented for the LIGO Length Sensing and Control (LSC) [1] and Alignment\nSensing and Control (ASC) [2] systems. In addition, the paper will describe how\nthese controls, along with the suspended optic controls [3], have been\nintegrated into the overall LIGO control and data acquisition system [4].",
    "arxiv_id": "physics/0111027",
    "authors": [
      "J. Heefner",
      "R. Bork",
      "R. Abbott"
    ],
    "categories": [
      "physics.ins-det",
      "physics.gen-ph",
      "physics.optics"
    ],
    "journal_ref": "eConf C011127 (2001) WEAP060",
    "title": "The LIGO Interferometer Sensing and Control System",
    "url": "https://arxiv.org/abs/physics/0111027"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "3c2621b2-f3d5-4cf3-b0cf-79f3cdca87f3",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}