Double-layer ion acceleration triggered by ion magnetization in expanding radiofrequency plasma sources

Journal Article · Mon Oct 04 00:00:00 EDT 2010 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3499653· OSTI ID:21466994

Takahashi, Kazunori ^[1]; Charles, Christine; Boswell, Rod W ^[2]; Fujiwara, Tamiya ^[1]

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1. Department of Electrical and Electronic Engineering, Iwate University, Morioka 020-8551 (Japan)
2. Space Plasma, Power and Propulsion Group, Research School of Physics and Engineering, Australian National University, Canberra 0200 (Australia)

Ion energy distribution functions downstream of the source exit in magnetically expanding low-pressure plasmas are experimentally investigated for four source tube diameters ranging from about 5 to 15 cm. The magnetic-field threshold corresponding to a transition from a simple expanding plasma to a double layer-containing plasma is observed to increase with a decrease in the source tube diameter. The results demonstrate that for the four geometries, the double layer and the accelerated ion beam form when the ion Larmour radius in the source becomes smaller than the source tube radius, i.e., when the ions become magnetized in the source tube.

• OSTI ID: 21466994
• Journal Information: Applied Physics Letters, Vol. 97, Issue 14; Other Information: DOI: 10.1063/1.3499653; (c) 2010 American Institute of Physics; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ACCELERATION
CHARGED-PARTICLE TRANSPORT
ENERGY SPECTRA
ION BEAMS
IONS
LAYERS
MAGNETIC FIELDS
MAGNETIZATION
PLASMA
PLASMA EXPANSION
PLASMA PRESSURE
PLASMA SHEATH
RADIOWAVE RADIATION
BEAMS
CHARGED PARTICLES
ELECTROMAGNETIC RADIATION
EXPANSION
RADIATION TRANSPORT
RADIATIONS
SPECTRA