{
  "annotation_id": "31b136d5-1d43-47cf-aad5-499f24d147a2",
  "date_created": "2026-03-02T18:00:50.368000Z",
  "date_modified": "2026-03-02T18:00:50.368000Z",
  "file_hash": "13c3241ddd15af67fb50cdbfb4a3721d834fb6d9af7fe08fc70760b89e2f71b3",
  "private": false,
  "record": {
    "abstract": "We report on measurements of charge transfer in GEM structures in high\nmagnetic fields. These were performed in the framework of the R\u0026D work for a\nTime Projection Chamber at a future Linear Collider. A small test chamber has\nbeen installed into the aperture of a superconducting magnet with the GEM\nstructures mounted perpendicular to the B field direction. The charge transfer\nis derived from the electrical currents monitored during irradiation with an\n${}^{55}$Fe source. No severe loss of primary ionisation charge is observed,\nbut an improved ion feedback suppression is achieved for high magnetic fields.\nAdditionally, the width of the charge cloud released by individual ${}^{55}$Fe\nphotons is measured using a finely segmented strip readout after the triple GEM\nstructure. Charge widths between 0.3 and 0.5 mm RMS are observed, which\noriginate from the charge broadening inside the GEM readout. This charge\nbroadening is only partly suppressed at high magnetic fields.",
    "arxiv_id": "physics/0402121",
    "authors": [
      "M. Killenberg",
      "S. Lotze",
      "J. Mnich",
      "A. Muennich",
      "S. Roth",
      "F. Sefkow",
      "M. Tonutti",
      "M. Weber",
      "P. Wienemann"
    ],
    "categories": [
      "physics.ins-det"
    ],
    "doi": "10.1016/j.nima.2004.04.241",
    "title": "Charge Transfer and Charge Broadening of GEM Structures in High Magnetic   Fields",
    "url": "https://arxiv.org/abs/physics/0402121"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "9445b146-fb8d-401e-bd62-a71931cffce4",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}