Overview of probe diagnostics on the H-1 heliac

A complex of probe diagnostics allows extensive characterization of the pla sma parameters in the H-1 heliac. The probes used on H-1 include quadruple probes, poloidal and radial "fork" probes, a Mach probe, a 24-channel probe array, and a retarding field energy analyzer. This article provides detail s of the probe design and a brief description of the experimental technique s involved. Different techniques are compared. Sample results in two differ ent modes of confinement in H-1 are presented. The capabilities of the prob e diagnostics used in different combinations are discussed. (C) 1999 Americ an Institute of Physics. [S0034-6748(99)52201- 6].