Passive Superconductor a Viable Method of Controlling Magnetization Multipoles in the SSC Dipole

  • Michael A. Green

Abstract

At injection, the magnetization of the superconductor produces the dominant field error in the SSC dipole magnets. The field generated by magnetization currents in the superconductor is rich in higher symmetric multipoles (normal sextupole, normal decapole, and so on). Pieces of passive superconductor properly located within the bore of the dipole magnet can cancel the higher multipoles generated by the SSC dipole coils. The multipoles generated by the passive superconductor (predominantly sextupole and decapole) are controlled by the angular and radial location of the superconductor, the volume of superconductor, and the size of the superconducting filaments within the passive conductor. This paper will present the tolerances on each of these factors. The paper will show that multipole correction using passive superconductor is in general immune to the effects of temperature and magnetization decay due to flux creep, provided that dipole superconductor and the passive correction superconductor are properly specified. When combined with a lumped correction system, the passive superconductor can be a viable alternative to continuous correction coils within the SSC dipoles.

Keywords

Vortex Titanium Manganese Niobium Titanium 

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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • Michael A. Green
    • 1
  1. 1.Lawrence Berkeley LaboratoryBerkeleyUSA

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