Test ion transport in a collisional, field-reversed configuration

Abstract

Diffusion of test-ions in a flux-coil generated, collisional, field-reversed configuration is measured via time-resolved tomographic reconstruction of Ar + optical emission in the predominantly nitrogen plasma. Azimuthal test ion diffusion across magnetic field lines is found to be classical during the stable period of the discharge. Test ion radial confinement is enhanced by a radial electric field, reducing the observed outward radial transport rate below predictions based solely on classical cross-field diffusion rates. Test ion diffusion is ∼500 m 2 s −1 during the stable period of the discharge. The electric field inferred from plasma potential measurements and from equilibrium calculations is consistent with the observed reduction in argon transport.

Special issue on transport inB-fields in low-temperature plasmas

“…In solar physics, the diffusion of plasmas across magnetic fields determines the dynamics of the corona, the solar wind and hence space weather at the earth [1]. Terrestrial thermo-nuclear fusion experiments have been particularly hampered by a lack of data, understanding and theory for decades [2,3]. Cross-field diffusion is particularly important in the formation and transport of beams of charged particles [4,5].…”