Study of a discharge created by radiation from a terahertz free electron laser in a nonuniform gas flow

This paper presents the results of a study of a discharge in a nonuniform flow noble gases (argon) created in a focused beam generated by a terahertz free electron laser (FEL) (frequency 2.3 THz). Data were obtained on the ranges of background gas pressures and gas injection rates at which the development of a discharge is possible. The dynamics of the discharge glow were studied in various wavelength ranges over a wide pressure range. It has been demonstrated that the plasma glows not only during FEL pulses, but also in the intervals between pulses of heating electromagnetic radiation.