Pulsed ionization chamber diagnostic studies of fissioning plasmas

The pulsed ionization chamber (PIC) plasma diagnostic technique is being applied to the study of the production and loss kinetics of nuclear seeded plasmas produced in a series of candidate fuel-gas/MHD working fluids. The study is part of an overall program underway at the University of Florida for determining the properties and characteristics of candidate materials for use with its AGCR/PGCR gas-core nuclear reactor/MHD space power concepts. The series of gases under study includes pure rare gases He, Ar, and Xe and molecular gas mixtures including fissionable UF/sub 6/ and other fluorine containing gases. The objective of the investigation is the determination of experimental values for electrical conductivities and plasma production and loss coefficients as functions of gas pressure and temperature. Trends established for such characteristics, determined initially at lower pressures and temperatures, i.e., 10-20 atm, 900-1000 K, should allow their values to be extrapolated, with confidence, into higher, more difficult to attain pressure and temperature regimes. The results obtained thus far support a T/sup -9/2/ temperature dependence for the plasma loss coefficients for pure rare gases and a T/sup -3/2/ temperature dependence, respectively, for molecular mixtures thereof