Experimental Test Of Whether Electrostatically Charged Micro-organisms And Their Spores Contribute To The Onset Of Arcs Across Vacuum Gaps
Abstract
Recently it was proposed [L.R. Grisham, A. vonHalle, A.F. Carpe, Guy Rossi, K.R. Gilton, E.D. McBride, E.P. Gilson, A. Stepanov, T.N. Stevenson, Physics of Plasma 19 023107 (2012)] that one of the initiators of vacuum voltage breakdown between condu cting electrodes might be micro-organisms and their spores, previously deposited during exposure to air, which tnen become electrostatically charged when an electric potential is applied across the vacuum gap. The note describes a simple experiment to compare the number of voltage-conditioning pulses required to reach the nominal maxium operating voltage across a gap between two metallic conductors in a vacuum, comparing cases in which biological cleaning was done just prior to pump-down with cases where this was not done, with each preceded by exposure to ambient air for three days. Based upon these results, it does not appear that air-deposited microbes and their spores constitute a major pathway for arc initiation, at least for exposure periods of a few days, and for vacuum gaps of a few millimeters, in the regime where voltage holding is usually observed to vary linearly with gap distance
- Authors:
- Publication Date:
- Research Org.:
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC)
- OSTI Identifier:
- 1129032
- Report Number(s):
- PPPL-4991
- DOE Contract Number:
- DE-ACO2-09CH11466
- Resource Type:
- Technical Report
- Resource Relation:
- Related Information: Published in Phys. Plasmas 20 , 124504 (2013)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Micro-organisms
Citation Formats
none,, and Grisham, Larry R. Experimental Test Of Whether Electrostatically Charged Micro-organisms And Their Spores Contribute To The Onset Of Arcs Across Vacuum Gaps. United States: N. p., 2014.
Web. doi:10.1063/1.4858895.
none,, & Grisham, Larry R. Experimental Test Of Whether Electrostatically Charged Micro-organisms And Their Spores Contribute To The Onset Of Arcs Across Vacuum Gaps. United States. https://doi.org/10.1063/1.4858895
none,, and Grisham, Larry R. 2014.
"Experimental Test Of Whether Electrostatically Charged Micro-organisms And Their Spores Contribute To The Onset Of Arcs Across Vacuum Gaps". United States. https://doi.org/10.1063/1.4858895. https://www.osti.gov/servlets/purl/1129032.
@article{osti_1129032,
title = {Experimental Test Of Whether Electrostatically Charged Micro-organisms And Their Spores Contribute To The Onset Of Arcs Across Vacuum Gaps},
author = {none, and Grisham, Larry R.},
abstractNote = {Recently it was proposed [L.R. Grisham, A. vonHalle, A.F. Carpe, Guy Rossi, K.R. Gilton, E.D. McBride, E.P. Gilson, A. Stepanov, T.N. Stevenson, Physics of Plasma 19 023107 (2012)] that one of the initiators of vacuum voltage breakdown between condu cting electrodes might be micro-organisms and their spores, previously deposited during exposure to air, which tnen become electrostatically charged when an electric potential is applied across the vacuum gap. The note describes a simple experiment to compare the number of voltage-conditioning pulses required to reach the nominal maxium operating voltage across a gap between two metallic conductors in a vacuum, comparing cases in which biological cleaning was done just prior to pump-down with cases where this was not done, with each preceded by exposure to ambient air for three days. Based upon these results, it does not appear that air-deposited microbes and their spores constitute a major pathway for arc initiation, at least for exposure periods of a few days, and for vacuum gaps of a few millimeters, in the regime where voltage holding is usually observed to vary linearly with gap distance},
doi = {10.1063/1.4858895},
url = {https://www.osti.gov/biblio/1129032},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Feb 24 00:00:00 EST 2014},
month = {Mon Feb 24 00:00:00 EST 2014}
}