Ionization and current growth in N/sub 2/ at very high electric field to gas density ratios

Journal Article · Mon May 01 00:00:00 EDT 1989 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.342651· OSTI ID:6475335

Gylys, V T; Jelenkovic, B M; Phelps, A V

Measurements and analyses have been made of electron impact ionization and of current growth in pulsed, low-current, prebreakdown discharges in parallel-plane geometry in N/sub 2/ at very high electric field to gas density ratios E/n and low products of the gas density n and electrode separation d. The E/n range and nd ranges were 1<3 x 10/sup 20/ m/sup -2/ (or 0.02<1 Torr cm, where p is pressure) and were below breakdown values. Measurements were made of the transported charge on the time scales of electron transit, ion transit, and metastable decay. Measurements were also made of the growth of steady-state discharge currents as a function of discharge voltage. The contributions of avalanches resulting from ion- and metastable-induced secondary electrons were determined from the ratio of electron-excited N/sup +//sub 2/ 391.4-nm emission integrated over all avalanches to the integrated emission during the laser-initiated electron pulse. Calculations based on ionization by electrons only show good agreement with the measured charge transported during the electron avalanche and with the current multiplication. Analysis of 391.4-nm emission data and of charge transported at E/ngreater than or equal to10 kTd and voltages near breakdown using the assumption of electron impact ionization leads to large apparent secondary electron yields at the cathode which increase significantly with nd.

• Research Organization: Joint Institute for Laboratory Astrophysics, University of Colorado and National Institute of Standards and Technology, Boulder, Colorado 80309-0440
• OSTI ID: 6475335
• Journal Information: J. Appl. Phys.; (United States), Vol. 65:9
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
ELECTRIC DISCHARGES
ELECTRIC CURRENTS
NITROGEN
BREAKDOWN
DENSITY
ELECTRODES
ELECTRON BEAMS
ELECTRON DRIFT
GASES
IONIZATION
LASERS
MOLECULES
PULSES
SCALING LAWS
STEADY-STATE CONDITIONS
BEAMS
CURRENTS
ELEMENTS
FLUIDS
LEPTON BEAMS
NONMETALS
PARTICLE BEAMS
PHYSICAL PROPERTIES
420800* - Engineering- Electronic Circuits &amp; Devices- (-1989)