APPENDIX A

                     UPLAZ-2 PROGRAM


        The UPLAZ-2 program calculates the composition of an uranium plasma as a function of plasma pressure and temperature. The plasma is assumed to be in local thermodynamic equilibrium. The uranium ion partition functions are calculated using the isoelectronic approximation to compute statistical weights and energy levels of the excited states. Corrections for the lowering of atomic and ionic ionization potentials are included. A maximum of twelve degrees of ionization can be calculated. The individual plasma species are computed in terms of particle density, partial pressure, and per cent of total particles.

        The input data consist of one card per case containing the pressure and temperature in 2E12.6 format as follows:

               Columns 1-12   P (atmospheres)

               Columns 13-24 T (OK)

Multiple cases can be run consecutively by stacking one data card per case. The output data include  the total particle density, maximum degree of ionization, lowering


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