TY - JOUR
T1 - Phenomenology of subnanosecond gas discharges at pressures below one atmosphere
AU - Krompholz, Herman G.
AU - Hatfield, Lynn L.
AU - Neuber, Andreas A.
AU - Kohl, Kevin P.
AU - Chaparro, Jordan E.
AU - Han-Yong, Ryu
N1 - Funding Information:
Manuscript received August 31, 2005; revised December 22, 2005. This work was supported by the Air Force Office of Scientific Research.
PY - 2006
Y1 - 2006
N2 - Volume breakdown and surface flashover in quasi-homogeneous applied fields in 10-5 to 600 torr argon and dry air are investigated, using voltage pulses with 150 ps risetime, <1ns duration, and up to 150 kV amplitude into a matched load. The test system consists of a transmission line, a transition to a biconical section, and a test gap, with gap distances of about 1mm. The arrangement on the other side of the gap is symmetrical. Diagnostics include fast capacitive voltage dividers, for determination of voltage waveforms in the gap, and conduction current waveforms through the gap. X-ray diagnostics use a scintillator-photomultiplier combination with different absorber foils yielding coarse spectral resolution. Optical diagnostics include use of a streak camera to get information on the discharge channel geometry and dynamics, and temporally resolved measurements with photomultipliers. Breakdown delay times are on the order of 100-400 ps, with minima occurring in the range of several 10torr. X-ray emission extends to pressures >100 torr, indicating the role of runaway electrons during breakdown. Maximum X-ray emission coincides with shortest breakdown delay times at several 10 torr. Simple modeling using the average force equation and cross sections for momentum transfer and ionization supports the experimental results.
AB - Volume breakdown and surface flashover in quasi-homogeneous applied fields in 10-5 to 600 torr argon and dry air are investigated, using voltage pulses with 150 ps risetime, <1ns duration, and up to 150 kV amplitude into a matched load. The test system consists of a transmission line, a transition to a biconical section, and a test gap, with gap distances of about 1mm. The arrangement on the other side of the gap is symmetrical. Diagnostics include fast capacitive voltage dividers, for determination of voltage waveforms in the gap, and conduction current waveforms through the gap. X-ray diagnostics use a scintillator-photomultiplier combination with different absorber foils yielding coarse spectral resolution. Optical diagnostics include use of a streak camera to get information on the discharge channel geometry and dynamics, and temporally resolved measurements with photomultipliers. Breakdown delay times are on the order of 100-400 ps, with minima occurring in the range of several 10torr. X-ray emission extends to pressures >100 torr, indicating the role of runaway electrons during breakdown. Maximum X-ray emission coincides with shortest breakdown delay times at several 10 torr. Simple modeling using the average force equation and cross sections for momentum transfer and ionization supports the experimental results.
KW - Gas discharges
KW - High overvoltages
KW - Runaway electrons
KW - Subnanosecond regime
UR - http://www.scopus.com/inward/record.url?scp=34547910335&partnerID=8YFLogxK
U2 - 10.1109/TPS.2006.875824
DO - 10.1109/TPS.2006.875824
M3 - Article
AN - SCOPUS:34547910335
SN - 0093-3813
VL - 34
SP - 927
EP - 936
JO - IEEE Transactions on Plasma Science
JF - IEEE Transactions on Plasma Science
IS - 3 PART 3
ER -