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Bremsstrahiung Energy Losses

        The energy balance equation (8.46) relates energy production from fission and energy loss by diffusion. If there were no radiation losses from the plasma, the source term would represent the kinetic energy of the fission fragments. However, since the charged particles in the dense, high temperature plasma will lose energy by bremsstrahlung, the energy production must be sufficient to offset these radiation losses. To explicitly account for the bremsstrahlung, the source term in equation (8.46) is written as


               S(r) = S   (r) - B(r)                (8.62)
                       ff

where


        S(r) = net energy available for heating the plasma

      Sff(r) = fission fragment energy

        B(r) = bremsstrahlung energy


The bremsstrahlung energy is given by (71) B(r) = 5.35 x 10 34C (r) . Ci(r)Z2 /-r7 N'   (r) watts/cc e                       1                TOT
                                                    (8.63)

where C (r) and C. (r) are the electron and ion concentrations,
       e         1.
respectively, and N TOT(r) is the total particle density. The net energy production, S(r), is a parameter evaluated