An actively shielded superconducting magnet having a dipole shim coil for adjusting and fine-tuning an external or far fringe magnetic field produced by a main coil of the magnet. An active shield coil is coupled to the main coil in reverse polarity and produces a magnetic field when energized that opposes the far fringe field to substantially reduce the far fringe field. The dipole shim coil is electrically isolated from the active shield and main coils of superconducting magnet, and produces a magnetic field when energized that provides for the fine adjustment of any residual far fringe field.

 
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> Method and apparatus for discrete shielding of volume RFcoil arrays

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