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of the Boltzmann equation to solid core reactors can be characterized by two features:  (1) the assumption that epithermal neutrons are slowed down by collisions with stationary nuclei and (2) the methods of therma2ization theory are used to treat the effects of nuclear moLion and chemical binding on thermal neutron collisions.

        In order to properly apply the Boltzmann equation to neutrons in plasma core reactor: several modifications are necessary. The need for these modifications is due to the extremely high temperatures of the plasma core reactor, as compared to solid core reactor temperatures. Tempera-tures on the order of 100,0001K are anticipated in the plasma core reactor. Scattering and absorbing nuclei, at this elevated temperature have an energy kT = 8.6 eV. Recalling that scattering and absorbing nuclei in a solid core reactor have a maximum energy of about 0.05 eV and

0.26 eV respectively, it is clear that nuclear motion becomes a more important consideration in a plasma core reactor. To formally account for the possible effects of this increased nuclear motion, the usual form of the Boltzmann equation (2.1) is modified to include the dependence of collision processes on the relative speed. The following symbols for the several velocities are used: