Effect of broadband microwave radiation on the performance of a conventional B-minimum geometry electron cyclotron resonance ion source

Journal Article · Wed Mar 15 04:00:00 EST 2006 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2174830· OSTI ID:20778971

Kawai, Y; Alton, G D; Tarvainen, O; Suominen, P; Koivisto, H ^[1]

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1. Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States)

The performances of electron cyclotron resonance ion sources can be enhanced by increasing the physical sizes or numbers of resonant zones embedded within their plasma volumes. Broadband rf power offers a simple, cost effective alternative for increasing the sizes of electron cyclotron resonance (ECR) zones in conventional minimum-B geometry sources over independently powered narrow bandwidth, multiple discrete frequency schemes. In this report, the charge-state enhancing effects of broadband microwave radiation are first demonstrated by comparing the high charge states of Ar ion beams produced by powering a conventional minimum-B geometry, 6.4 GHz ECR ion source with broadband microwave radiation {l_brace}200 MHz [full width at half maximum (FWHM)]{r_brace} with those produced by conventional bandwidth [{approx}1.5 MHz (FWHM)] radiation. The results of these studies show that high-charge-state beams (e.g., Ar{sup 11+}) can be enhanced by factors >2 with broadband microwave radiation over those powered with narrow bandwidth radiation at the same power level, with or without voltage applied to the biased disk. The high charge states exhibit an anomalously strong increase in intensity at an optimum pressure with broadband microwave radiation.

• OSTI ID: 20778971
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 3 Vol. 77; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ARGON IONS
CHARGE STATES
ECR ION SOURCES
ELECTRON CYCLOTRON-RESONANCE
GEOMETRY
GHZ RANGE 01-100
ION BEAMS
MHZ RANGE
MICROWAVE RADIATION
PERFORMANCE