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is evaluated repeatedly until the desired degree of accuracy is obtained. The electron density is then given by


                      ee   N
                         e  TOT

From equation (4.12),


                C
         S    13e         and N =C NTOT
           C'.                 1    13TOT
                     i-i

             i=2   CiFrom equation (4.7-i), Ni+1 = K N e/Ni for i = 1, 2, . . 12, gives the particle densities N2, N3, . . ., N13. The particle densities Ne, N1, N2, . ., N13 then completely describe the uranium plasma composition.


Low Temperature Equations

        For temperatures less than about 10,0001K, the iterative method for solving equation (4.14) does not readily converge. Although uranium is not highly ionized at temperatures below 10,0001K, a knowledge of the low temperature uranium plasma composition is necessary in order to describe initial or startup conditions in a gaseous-core reactor. A different mathematical formulation is used to calculate the plasma composition at low temperatures.