Photopreionization of the 3371-Å pulsed N2laser

Photopreionization of the 3371-Å pulsed N
2
laser by use of a seed gas of low ionization threshold and flashlamp excitation is observed to result in increased laser output and reproducibility. Preionization also increases the range of permissible operating pressures, enabling operation with atmospheric-pressure mixtures of N
2
and He without reduced intensity.