Uranium plasma emission at gas-core reaction conditions

The results of uranium plasma emission produced by two methods are reported. For the first method a ruby laser was focused on the surface of a pure 238U sample to create a plasma plume with a peak plasma density of about 1020 cm-3 and a temperature of about 38,6000K. The absolute intensity of the emitted radiation, covering the range from 300 to 7000 A was measured. For the second method, the uranium plasma was produced in a 20 kilovolt, 25 kilojoule plasma-focus device. The 2.5 MeV neutrons from the D-D reaction in the plasma focus are moderated by polyethylene and induce fissions in the 235U. Spectra of both uranium plasmas were obtained over the range from 30 to 9000 A. Because of the low fission yield the energy input due to fissions is very small compared to the total energy in the plasma