The lasing medium is enclosed in a tube lined with uranium-235 and subjected to high neutron flux in a nuclear reactor core.
The fission fragments of the uranium create excited plasma with inverse population of energy levels, which then lases.
In 1975 it was estimated, by George Chapline and Lowell Wood from the Lawrence Livermore National Laboratory, that “pumping a 10-keV (0.12-nm) laser would require around a watt per atom” in a pulse that was “10−15 seconds x the square of the wavelength in angstroms.” As this problem was unsolvable with the materials at hand and a laser oscillator was not working, research moved to creating pumps that used excited plasma.
of this plan found many faults in such an approach and questioned aspects such as the power, range, accuracy, politics, and cost of such deployments.
The Livermore method was to remove the outer electrons in heavy atoms to create a “neon-like” substance.
A launch using laser propulsion requires high intensity, short pulses, good quality[Define?
[3] The characteristics of the nuclear pumped laser make it ideal for applications in deep-cut welding, cutting thick materials, the heat treating of metals, vapor deposition of ceramics, and the production of sub-micron sized particles.
[4] Titled Project Excalibur, the program was a part of President Reagan's Strategic Defense Initiative.