Trisops

Trisops was an experimental machine for the study of magnetic confinement of plasmas with the ultimate goal of producing fusion power. The configuration was a variation of a compact toroid, a toroidal (doughnut-shaped) structure of plasma and magnetic fields with no electromagnetic coils or electrodes penetrating the center. It lost funding in its original form in 1978.

The configuration is produced by combining two individual toroids produced by two conical θ pinch guns, located at either end of a length of Pyrex pipe with a constant guide magnetic field. The toroidal currents in the toroids are in opposite directions, so that they repel each other. After coming to an equilibrium, they are compressed adiabatically by increasing the external field.