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Title: Collisional damping of helicon waves in a high density hydrogen linear plasma device

Abstract

In this paper, we investigate the propagation and damping of helicon waves along the length (~50 cm) of a helicon-produced 20 kW hydrogen plasma ( ~1-2 1019 m-3, ~1-6 eV, H2 8 mTorr) operated in a magnetic mirror configuration (antenna region: 50-200 G and mirror region: 800 G). Experimental results show the presence of traveling helicon waves (~10 G and ~ 10-15 cm) propagating away from the antenna region which become collisionally absorbed within 40 to 50 cm. We describe the use of the WKB method to calculate wave damping and provide an expression to assess its validity based on experimental measurements. By comparing theory and experiment, we show that for the conditions associated with this paper classical collisions are sufficient to explain the observed wave damping along the length of the plasma column. Based on these results, we provide an expression for the scaling of helicon wave damping relevant to high density discharges and discuss the location of surfaces for plasma-material interaction studies in our device (MAGPIE).

Authors:
 [1];  [2]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. Research School of Physics and Engineering ANU, Canberra (Australia)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1347309
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Plasma Sources Science and Technology
Additional Journal Information:
Journal Volume: 25; Journal Issue: 5; Journal ID: ISSN 0963-0252
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Caneses, Juan F., and Blackwell, Boyd D. Collisional damping of helicon waves in a high density hydrogen linear plasma device. United States: N. p., 2016. Web. doi:10.1088/0963-0252/25/5/055027.
Caneses, Juan F., & Blackwell, Boyd D. Collisional damping of helicon waves in a high density hydrogen linear plasma device. United States. doi:10.1088/0963-0252/25/5/055027.
Caneses, Juan F., and Blackwell, Boyd D. Wed . "Collisional damping of helicon waves in a high density hydrogen linear plasma device". United States. doi:10.1088/0963-0252/25/5/055027. https://www.osti.gov/servlets/purl/1347309.
@article{osti_1347309,
title = {Collisional damping of helicon waves in a high density hydrogen linear plasma device},
author = {Caneses, Juan F. and Blackwell, Boyd D.},
abstractNote = {In this paper, we investigate the propagation and damping of helicon waves along the length (~50 cm) of a helicon-produced 20 kW hydrogen plasma ( ~1-2 1019 m-3, ~1-6 eV, H2 8 mTorr) operated in a magnetic mirror configuration (antenna region: 50-200 G and mirror region: 800 G). Experimental results show the presence of traveling helicon waves (~10 G and ~ 10-15 cm) propagating away from the antenna region which become collisionally absorbed within 40 to 50 cm. We describe the use of the WKB method to calculate wave damping and provide an expression to assess its validity based on experimental measurements. By comparing theory and experiment, we show that for the conditions associated with this paper classical collisions are sufficient to explain the observed wave damping along the length of the plasma column. Based on these results, we provide an expression for the scaling of helicon wave damping relevant to high density discharges and discuss the location of surfaces for plasma-material interaction studies in our device (MAGPIE).},
doi = {10.1088/0963-0252/25/5/055027},
journal = {Plasma Sources Science and Technology},
number = 5,
volume = 25,
place = {United States},
year = {Wed Sep 28 00:00:00 EDT 2016},
month = {Wed Sep 28 00:00:00 EDT 2016}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 4works
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