In the present work, we have suggested a technical solution of a CO laser facility for industrial separation of uranium used in the production of fuel for nuclear power plants. There has been used a method of laser isotope separation of uranium, employing condensation repression in a free jet. The laser operation with nanosecond pulse irradiation can provide acceptable efficiency in the separating unit and the high effective coefficient of the laser with the wavelength of 5.3？ m. Receiving a uniform RF discharge under medium pressure and high Mach numbers in the gas stream solves the problem of an electron beam and cryogenic cooler of CO lasers. The laser active medium is being cooled while it is expanding in the nozzle; a low-current RF discharge is similar to a non-self-sustained discharge. In the present work, we have developed a calculation model of optimization and have defined the parameters of a mode-locked CO laser with an RF discharge in the supersonic stream. The CO laser average power of 3？kW is sufficient for efficient industrial isotope separation of uranium at one facility. 1. Introduction Researches that have been done recently have resulted in a breakthrough method of isotope laser separation of uranium employing condensation repression in a free jet [1, 2]. The cost of uranium enrichment for nuclear power plants fuel realized by this method can be twice lower than by ultracentrifuges [2]. Under low temperatures and low pressures in the free supersonic jet, dimers are being effectively produced, which consist of isotopes iUF6 and the carrier gas G. Irradiation of the 5.3？μm wavelength is employed for the selective excitation of 235UF6 due to a shift in the absorption bands of 235UF6 and 238UF6. The dimers 238UF6:G formed in the supersonic jet and tend to stay in the jet core. The dimers with the excited molecule break down quickly due to the vibrational energy transiting to the fragment kinetic energy. As a result, molecules 235UF6 escape from the core to the jet rim [2]. The energy consumption per one dimer is only 0.23？eV. Small absorption cross section of 235UF6 requires a separating unit with a long length and the nanosecond pulse irradiation with a high power peak. This results in high productivity in the separating block and high efficiency of the mode-locked CO laser with the wavelength of 5.3？μm. The average power of several kilowatts and the pulse repetition rate of 10？MHz are sufficient for efficient industrial isotope separation of uranium at one facility. When the laser having the power of several kilowatts operates in a
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