The NPL allows a laser system with an extremely large excitation volume and a “built-in” energy source. This unique possibility could lead to a wide variety of applications that require high power sources. Here, two examples are discussed: space applications and laser fusion.

The power demand for future space missions will significantly increase in the twenty-first century, especially for such missions as establishing lunar and Mars

bases, creating space industrialization, and developing new propulsion systems. NASA-Langley and University of Illinois researchers have considered the use of NPLs to provide a cost-effective, enabling technology that could beam power in the form of a laser beam to remote users in space [78]. These users could then convert the laser energy into either electricity or propulsion. The space-based reactor power station could be placed in a high nuclear-safe orbit (as illustrated in Fig. 13.5).

The Laboratory Microfusion Facility (LMF), shown in Fig. 13.6, has been proposed to study inertial confinement fusion (ICF) targets with an MJ-scale laser

to obtain reactor-grade gains. An advanced solid-state laser is the prime candidate as the driver for the LMF. However, researchers at the University of Illinois have developed a preliminary conceptual design for an alternate approach using NPLs [70, 71]. In this concept, a pulsed fission reactor is used to excite an O2([11] [12]A)-I2NPL. An important potential advantage of the NPL driver is that projected costs are significantly lower than for a conventional solid-state laser. Another key advantage is that the LMF NPL experiment would provide a direct path to the development of a high-efficiency commercial reactor using the neutron feedback NPL driver approach [71]. In that case, the fission reactor would be eliminated with neutrons from the target implosion directly driving the NPL. This approach and a variant on it using D-3He instead of conventional D-T targets are discussed in [78].

Acknowledgments As indicated by the references, many people have made significant contri­butions to NPL research in the United States. This chapter was largely adapted, with some additions (especially regarding theoretical advances) from a prior review in the Journal of Laser and Particle Beams [2], and a presentation at the ANS Conference on Fifty Years with Nuclear Fission authored by Miley, R. DeYoung, D. McArthur, and M. Prelas [1].

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