SP-1

Supported Spherator 1 (SP-1, sometimes called just Spherator) was a device built at PPPL. SP-1 had a 0.75 m diameter stainless steel vacuum vessel. It had a 0.325 m radius internal ring that was mechanically supported by six supports with 1/8" stainless rods (around 3 mm diameter) and was water cooled. This ring had a 72 kA current and produced a magnetic field of 0.1T.

The objectives of the experiment were to determine how the plasma is lost, to deterimine whether the plasma is unstable, and to study the production and the generation of plasmas in the spherator geometry.

SP-1 was later modified to reduce the feedthrough from 3 cm to 4 mm diameter by eliminating the water cooling system. The supports were also substituted with smaller rods (1 mm diameter). These modifications allowed the average flight distance of the particles (the distance before hitting a support or the feedthrough) to be increased from 10m to 50m.