FUEL PRECONDITIONING STUDIES FOR E-BEAM FUSION-TARGETS

Fuel temperature and density conditions, achieved during the preheat phase of electron-beam fusion compression experiments, must be accurately known to understand experimental results via numerical simulations. We present studies of discharge preheating in a simplified cylindrical geometry which compare measured quantities with results from the one-dimensional Lagrangian CHARTB magnetohydrodynamic code. Experimental measurements included schlieren photography and ultraviolet through visible time- and space-resolved spectroscopy in various configurations. It is seen that an 8-kA 500-ns heating pulse in 100 Torr of D2+10% O2 produces 10-12 eV temperatures, 1018 cm-3 electron densities, and 7×105 cm/s expansion velocities in the heated discharge channel. These results are consistent with previous claims for neutron-producing targets, although the target geometry is different.