Direct nuclear pumping of a helium−xenon laser

Excitation of a He−Xe laser was achieved by nuclear pumping, i.e., fission products interacted directly with the lasing gas and a portion of their energy was emitted as laser light. The transition observed is most likely the Xe 5d[7/2]03−6p[5/2]2, 3.508 μm. The He−Xe gas mixture ratio was 20 : 1 at a total pressure of 200 Torr. The light output exhibited a threshold effect and had the same characteristic waveform as the fission fragment flux above the threshold level. Laser output duration was approximately 150 μsec.