{
  "annotation_id": "805d11fa-8f7e-4a4f-81f4-caccc1460812",
  "date_created": "2026-03-02T18:00:36.336000Z",
  "date_modified": "2026-03-02T18:00:36.336000Z",
  "file_hash": "81d39142e562c233d6032fed53708585c0c199a05c3603c4e4d3cc3712ef83fb",
  "private": false,
  "record": {
    "abstract": "We describe the construction of a prototype hybrid permanent magnet dipole\nand quadruple. The magnet consists of two concentric rings of SmCo magnetic\nmaterial 5 cm in length. The outer ring is made of 16 uniformly magnetized\nblocks assembled as a Halbach dipole and the inner ring has 32 blocks oriented\nin a similar fashion so as to generate a quadruple field. The resultant\nsuperimposed field is an offset quadruple field which allows us to center the\nfield on the high-energy beam in the interaction region of the PEPII B factory.\nThe dipole blocks are glued to the inside surface of an outer support collar\nand the quadruple blocks are held in a fixture that allows radial adjustment of\nthe blocks prior to potting the entire assembly with epoxy. An extensive\ncomputer model of the magnet has been made and from this model we developed a\ntuning algorithm that allowed us to greatly reduce the n=3-17 harmonics of the\nmagnet.",
    "arxiv_id": "physics/0110089",
    "authors": [
      "M. Sullivan",
      "G. Bowden",
      "S. Ecklund",
      "D. Jensen",
      "M. Nordby",
      "A. Ringwall",
      "Z. R. Wolf"
    ],
    "categories": [
      "physics.acc-ph"
    ],
    "journal_ref": "Conf.Proc.C970512:3330,1997",
    "title": "Results from a Prototype Permanent Magnet Dipole-Quadrupole Hybrid for   the PEP-II B-Factory",
    "url": "https://arxiv.org/abs/physics/0110089"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "2883b5d6-7de0-4d51-961f-4d9765717132",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}