TY - GEN
T1 - Ultrafast gas breakdown at pressures below one atmosphere
AU - Krompholz, H.
AU - Hatfield, L.
AU - Neuber, A.
AU - Chaparro, J.
AU - Ryu, H. Y.
AU - Justis, W.
PY - 2006
Y1 - 2006
N2 - Gas breakdown in quasi homogeneous electric fields with amplitudes of up to 3 MV/cm is investigated. The setup consists of a RADAN 303 A pulser and pulse sheer SN 4, an impedance-matched oil-filled coaxial line with a lens-transition to a biconical line in vacuum or gas, and an axial or radial gap with a width on the order of mm, with a symmetrical arrangement on the other side of the gap. Capacitive voltage dividers allow to determine voltage across as well as conduction current through the gap, with a temporal resolution determined by the oscilloscope sampling rate of 20 GS/s and an analog bandwidth of 6 GHz. The gap capacitance charging time and voltage risetime across the gap is less than 250 ps. Previous experiments at TTU with a slightly larger risetime have shown that breakdown is governed by runaway electrons, with multi-channel formation and high ionization and light emission in a thin cathode layer only. In argon and air, time constants for the discharge development have been observed to have a minimum of around 100 ps at several 10 torr. A qualitative understanding of the observed phenomena and their dependence on gas pressure is based on explosive field emission and gaseous ionization for electron runaway conditions.
AB - Gas breakdown in quasi homogeneous electric fields with amplitudes of up to 3 MV/cm is investigated. The setup consists of a RADAN 303 A pulser and pulse sheer SN 4, an impedance-matched oil-filled coaxial line with a lens-transition to a biconical line in vacuum or gas, and an axial or radial gap with a width on the order of mm, with a symmetrical arrangement on the other side of the gap. Capacitive voltage dividers allow to determine voltage across as well as conduction current through the gap, with a temporal resolution determined by the oscilloscope sampling rate of 20 GS/s and an analog bandwidth of 6 GHz. The gap capacitance charging time and voltage risetime across the gap is less than 250 ps. Previous experiments at TTU with a slightly larger risetime have shown that breakdown is governed by runaway electrons, with multi-channel formation and high ionization and light emission in a thin cathode layer only. In argon and air, time constants for the discharge development have been observed to have a minimum of around 100 ps at several 10 torr. A qualitative understanding of the observed phenomena and their dependence on gas pressure is based on explosive field emission and gaseous ionization for electron runaway conditions.
UR - http://www.scopus.com/inward/record.url?scp=50549101331&partnerID=8YFLogxK
U2 - 10.1109/CEIDP.2006.311996
DO - 10.1109/CEIDP.2006.311996
M3 - Conference contribution
AN - SCOPUS:50549101331
SN - 1424405475
SN - 9781424405473
T3 - Annual Report - Conference on Electrical Insulation and Dielectric Phenomena, CEIDP
SP - 569
EP - 572
BT - 2006 Annual Report - Conference on Electrical Insulation and Dielectric Phenomena, CEIDP
T2 - 2006 Conference on Electrical Insulation and Dielectric Phenomena, CEIDP
Y2 - 15 October 2006 through 18 October 2006
ER -