Lasing due to transitions in the Xe atom on excitation of a Kr–Xe mixture and of pure xenon with uranium fission fragments

An investigation was made of a high-pressure quasi-cw laser operating on the basis of the 5d–6p transitions in the Xe atom. The duration of the output radiation pulses was up to 7 ms. Competition between the lasing lines at λ = 2.63 and 2.8 μm was observed in a Kr–Xe mixture. The maximum output power was 150 W (corresponding to the efficiency of ~0.2%) and it was obtained for the 2.63 μm line in a mixture of the Kr : Xe = 50 : 1 composition when the pressure was 0.35 bar. The lasing threshold was reached when the thermal neutron flux was about 3×10¹² cm^-2 s^-1. Lasing of pure Xe at pressures of 0.13–0.6 bar was observed at the 3.51 μm wavelength (in this case the maximum output radiation power was about 90 W).