The ion velocity distribution function in a current-free double layer

Date

2005-08-26

Authors

Keesee, Amy M.
Scime, Earl E.
Charles, Christine
Meige, Albert
Boswell, Rod

Journal Title

Journal ISSN

Volume Title

Publisher

American Institute of Physics

Abstract

A portable, low-power, diode laser-based laser-induced fluorescence(LIF)diagnostic incorporating a heated iodine cell for absolute wavelength reference was installed on the Chi-Kung helicon source [K. K. Chi, T. E. Sheridan, and R. W. Boswell, Plasma Sources Sci. Technol.8, 421 (1999)] to measure the ion velocity distribution function of argon ions as they transited a current-free double layer (DL) created where the solenoidal magnetic field diverges at the junction of the plasma source and the diffusion chamber. Based on LIFmeasurements of the transiting ion beam energy, the strength of the potential drop across the DL increases with decreasing neutral pressure and increasing magnetic field strength in the source. The location of the double layer also moves further downstream of the helicon source with increasing pressure. LIFmeasurements of the ion beam energy were found to be in good agreement with measurements obtained with a retarding field energy analyzer and also with numerical predictions.

Description

Keywords

Keywords: Diffusion chamber; Double layer (DL); Helicon source; Laser-induced fluorescence (LIF); Argon; Fluorescence; Helicons; Ion beams; Magnetic field effects; Semiconductor junctions; Semiconductor lasers

Citation

Source

Physics of Plasmas

Type

Journal article

Book Title

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DOI

10.1063/1.2033647

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