Electron beam volume discharge formation under atmospheric pressure in gases

It has been shown that the use of gas diodes with cathode electric field enhancement and voltage pulses having a short leading edge allow to form high-current subnanosecond electron beams. An electron beam appears at voltage pulse leading edge with duration at FWHM not more than 0.3 ns. On the beam current termination the discharge is usually continued in a quasi-stationary mode having a volume character. With a diode filled in with air under atmospheric pressure, beam current amplitude over similar to240 A at a pulse duration at FWHM of similar to0.2 ns and current density of similar to40 A/cm(2) was obtained. It has been also shown that at a small gas diode inductance the subnanosecond electron beams are formed in various gases in a wide pressure range (up to 6 atra in helium, and up to 4 atm in nitrogen). It has been established that with the new method an electron beam is formed due to critical field reached between an anode and plasma propagating from a cathode.