Stationary radiator in the 130 – 190 nm range based on a water vapour plasma

The characteristics of a continuous radiation source pumped by a longitudinal glow He – H₂O mixture discharge are presented. For a water vapour pressure of ~50 – 300 Pa and helium pressure of 1.0 – 8.0 kPa, the discharge under study was shown to emit radiation primarily in the 130 – 190 nm range. The optimal water vapour pressure lies in the range from 50 Pa to 150 Pa and the optimal partial helium pressure is 1.0 kPa. In the 3–50 mA range of the discharge current, the brightness of the main emission bands was observed to increase linearly with current.