Laser-induced preionization of a rare-gas halide discharge

Modest-energy-density KrF laser radiation has been used to provide uniform preionization in a 5-atm, 2.5 X 2.5- cm2 XeCl discharge. With approximately 1 mJ/cm2 of KrF radiation and the utilization of benzene additives at the level of a few parts in 10(6), an initial ionization density of approximately 10(7) cm(-3) is produced. The technique is scalable to large volumes and provides an effective means of controlling the pre ionization conditions.