Metastable argon atoms under significant neutral depletion in helicon plasmas by laser-induced fluorescence
- Creators
- Seo, B. H.
- Kim, J. H.
- You, S. J.
Abstract
We study the spatial distribution of the metastable-state argon atoms in high density helicon plasmas by means of laser-induced fluorescence. It is observed that the neutral argon in metastable-state has an anomalous radial distribution in density; it has a caldera-like shape radially, which is rare in typical low-temperature plasmas such as inductively coupled plasmas wherein the density increases toward the discharge center, as previously reported. The formation of the distribution can be explained as it forms by the combined effects of significant neutral depletion in high plasma density, off-axis electron-density distribution, and increasing diffusive loss toward the wall. To establish the assertion with the underlying physics, we calculate a simple global model and obtain the neutral density distribution in metastable-state under various conditions. The calculated results qualitatively agree with the experimental results.
Additional Information
© 2017 Elsevier B.V. Received 18 March 2017, Accepted 19 May 2017, Available online 24 May 2017.Additional details
- Eprint ID
- 78677
- Resolver ID
- CaltechAUTHORS:20170628-154557685
- Created
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2017-06-28Created from EPrint's datestamp field
- Updated
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2021-11-15Created from EPrint's last_modified field