Pumping of a coaxial nitrogen laser by a high-speed ionisation wave

An experimental demonstration was made of the effectiveness of an electric discharge, in the form of a high-velocity ionisation wave, in pumping a coaxial nitrogen laser operating at pressures of 5–120 Torr. The specific input energy delivered by this nitrogen-exciting wave was up to 2.1 J cm^-3 in a time of the order of 10 ns. Lasing action was observed at the wavelength 337.1 nm under superradiance conditions. The peak power of an output radiation pulse reached 100 kW and the half-maximum duration was 10 ns. The range of the nitrogen pressures with maximal energy deposition in the gas coincided with the range of the minimal amplitude attenuation of the ionisation wave moving along the discharge gap. The input energy, the velocity and attenuation of the high-speed ionisation wave, and the laser radiation intensity were determined as a function of the nitrogen pressure.