Figure A shows a simple magnet system comprised of a superconducting magnet, liquid helium dewar, and magnet support stand with helium vapor cooled current leads. Samples may be inserted into the magnetic field through the top of the dewar.

The magnet is mounted in the dewar by means of a support stand having a top plate, fiberglass support tubes, radiation baffles and a magnet mounting plate.

Counterflow helium vapor cooled current leads are used to conduct current to the magnet. Most of the heat generated in the leads is removed by the exhaust helium vapor flowing through them. Superconducting bus extensions on the leads may be incorporated that further reduce the heat generated in the dewar. These extensions are comprised of high transition temperature superconductive Nb3Sn tape sandwiched between copper strips and minimize the resistance of the bus bars. Radiant heat transfer into the helium is minimized by the nitrogen shielding and by the reflective baffles on the stand.

This type of system is used where the sample is to be immersed directly in the liquid helium. Other types of bore access arrangements are possible.

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