Gain measurements of Ar 2* excimer formed by high-pressure homogeneous discharge using plasma electrode

Highly homogeneous discharges have been obtained in pure Ar gas at high pressures of 10 - 20 atm by using a discharge device in which the surface discharge plasma from a dielectric surface is used as a preionizer and an electrode, the plasma electrode, aiming at an Ar 2 * excimer laser. The plasma electrode consists of a ceramic pipe with a length of 290 mm. The same electrode is used as a cathode and an anode. The electrode separation is 2 mm to generate the main discharge. The fluorescence of Ar 2 * excimer radiation has been investigated at a wavelength of around 126 nm. Time-resolved electron density and gain measurements have been carried out with nanosecond time-resolution. The electron density was over 16th power of ten at 10 atm. The optical gain at 126 nm has been observed at an Ar gas pressure of 15 atm, and the peak gain was 8.6%/cm.