Radial Electric Fields and Radial Currents in the Gas Dynamic Trap

In recent experiments on the GDT device the plasma confinement is shown to improve drastically with strong application of different potentials to the end plates and the limiter. We present experimental and theoretical description of how these potentials influence the plasma rotation, show that the measured plasma potentials indicate presence of global (m ~ 1) modes, and that sufficiently high gradients of potential provide the internal transport barrier by reducing convection.