Experimental tests of Langmuir probe theory for strong magnetic fields

• Published in: Plasma physics and controlled fusion Vol. 32; no. 13; pp. 1237 - 1248
• Main Authors: Pitts, R A, Stangeby, P C
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.12.1990; Institute of Physics
• Subjects: Exact sciences and technology; Physics; Physics of gases, plasmas and electric discharges; Physics of plasmas and electric discharges; Plasma diagnostic techniques and instrumentation; Tokamak; Electrostatic probe; Voltage current curve; Plasma diagnostic; Particle collection; Theoretical study; Magnetoactive plasma; Experimental study; Edge; Electrons
• ISSN: 0741-3335; 1361-6587
• DOI: 10.1088/0741-3335/32/13/004

The suppression of electron current to a single Langmuir probe immersed in a strongly magnetized plasma has been the subject of theoretical analysis since the original work of Bohm et al. Experimentally, studies of the phenomenon have been restricted to a comparison of measured data with analytic predictions of the I-V characteristic. Both theory and experiment show that the simple exponential law for electron collection assumed in the derivation of T sub(c) from the characteristic no longer holds for probe potentials above the floating potential. Certain theoretical aspects of net electron collection have also been tested and have been found to be in reasonable agreement with experiment, indicating that more effort may be justified in attempting to use this region of the characteristic as a diagnostic tool.