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Title: Conductivity tensor for anisotropic plasma in gyrokinetic theory

Abstract

Comprehensive non-invasive spectroscopic techniques and electrical measurements of the carbon arc revealed two distinguishable plasma synthesis regions in the radial direction normal to the arc axis. These regions, which are defined as the arc core and the arc periphery, are shown to have very different compositions of carbon species with different densities and temperatures. The colder arc periphery is dominated by carbon diatomic molecules (C-2), which are in the minority in the composition of the hot arc core. These differences are due to a highly non-uniform distribution of the arc current, which is mainly conducted through the arc core populated with carbon atoms and ions. Therefore, the ablation of the graphite anode is governed by the arc core, while the formation of carbon molecules occurs in the colder arc periphery. This result is consistent with previous predictions that the plasma environment in the arc periphery is suitable for synthesis of carbon nanotubes.

Authors:
 [1];  [2]
  1. Princeton Univ., Princeton, NJ (United States). Princeton Plasma, Physics Lab.
  2. Princeton Univ., Princeton, NJ (United States). Princeton Plasma, Physics Lab.; Andrews Univ., Berrien Springs, MI (United States)
Publication Date:
Research Org.:
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
OSTI Identifier:
1367353
Alternate Identifier(s):
OSTI ID: 1361888
Report Number(s):
PPPL-5368
Journal ID: ISSN 1070-664X; PHPAEN
Grant/Contract Number:
AGS1405225; NNH14AY11I; NNH14AY20I; NNH15AB17I; NNX16AC39G; NNX16AQ87G; AC02-09CH11466
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 24; Journal Issue: 5; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; arc discharge; arc nanomaterial synthesis; arc spectroscopy; carbon arc; arc structure; arc diagnostics; local thermodynamic-equilibrium; cathode deposit; plasma spectroscopy

Citation Formats

Porazik, Peter, and Johnson, Jay R. Conductivity tensor for anisotropic plasma in gyrokinetic theory. United States: N. p., 2017. Web. doi:10.1063/1.4983318.
Porazik, Peter, & Johnson, Jay R. Conductivity tensor for anisotropic plasma in gyrokinetic theory. United States. doi:10.1063/1.4983318.
Porazik, Peter, and Johnson, Jay R. Thu . "Conductivity tensor for anisotropic plasma in gyrokinetic theory". United States. doi:10.1063/1.4983318. https://www.osti.gov/servlets/purl/1367353.
@article{osti_1367353,
title = {Conductivity tensor for anisotropic plasma in gyrokinetic theory},
author = {Porazik, Peter and Johnson, Jay R.},
abstractNote = {Comprehensive non-invasive spectroscopic techniques and electrical measurements of the carbon arc revealed two distinguishable plasma synthesis regions in the radial direction normal to the arc axis. These regions, which are defined as the arc core and the arc periphery, are shown to have very different compositions of carbon species with different densities and temperatures. The colder arc periphery is dominated by carbon diatomic molecules (C-2), which are in the minority in the composition of the hot arc core. These differences are due to a highly non-uniform distribution of the arc current, which is mainly conducted through the arc core populated with carbon atoms and ions. Therefore, the ablation of the graphite anode is governed by the arc core, while the formation of carbon molecules occurs in the colder arc periphery. This result is consistent with previous predictions that the plasma environment in the arc periphery is suitable for synthesis of carbon nanotubes.},
doi = {10.1063/1.4983318},
journal = {Physics of Plasmas},
number = 5,
volume = 24,
place = {United States},
year = {Thu May 18 00:00:00 EDT 2017},
month = {Thu May 18 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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