Gas Discharge Point Source of UV Radiation Based on Argon– Copper Gas–Vapor Mixture

Abstract

The characteristics of a pulse periodic source of a long-range UV radiation with overvoltage pumping by a bipolar discharge of nanosecond duration between copper electrodes in argon at atmospheric pressure are investigated. Copper vapors were introduced into the discharge due to the ectonic mechanism when a sufficient amount of the electrode material vapors is introduced into the discharge gap due to microexplosions of inhomogeneities of the surface of metal electrodes in a strong electric field of an overvoltage highcurrent nanosecond discharge. The characteristics of an overvoltage nanosecond discharge at a distance between the electrodes of 2 mm are studied. The emission spectra of the discharge were analyzed, and the intensity of the UV radiation of a point emitter was optimized depending on the supply voltage of the highvoltage modulator and the repetition rate of discharge pulses. The identification of the emission spectra of plasma made it possible to establish the main excited plasma products that form the spectrum of the UV radiation of the plasma. The study of the spectral characteristics of plasma based on gas-vapor mixtures “copper– argon” showed that the most intense were the spectral resonance lines of the copper atom and ion. It was found that a space-uniform overvoltage nanosecond discharge was ignited between copper electrodes at an interelectrode distance of 2 mm. It was found that the maximum value of the average UV power at p(Ar) = 101 kPa was observed for the UV-A range.