The two pictures above show the inside of the superconducting magnet. The liquid nitrogen reservoir is mostly above the magnet with a cold finger extending down into the body of the magnet. The liquid nitrogen (77K) serves as a less expensive refrigerant to block infrared radiation from reaching the inner helium (4.2K) vessel.

Radiation shields on either side of the nitrogen cold finger also serve to block infrared radiation between layers of the cryostat.
The space between these layers is placed under high vacuum during normal operation.

The inner chamber is the liquid helium vessel and the superconducting solenoid wrapped in tape. The superconducting shims are visible on the outer surface.

In the bottom picture, a close-up of the charging plug and the quench resisters can be seen. The quench resistors protect the magnet during a quench by dissipating the energy stored in the superconducting coils.

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200 magnet

On March 13, 2014, the Varian Unity 200 was decommissioned due to failing electronics in the console. Subsequently, we took apart another magnet.

Thanks to Ben Geisbauer, Sean Murray, and Jason Radde, we have these new images.

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300 magnet

Then we had this spare 300 magnet, now on display in our facility.