Operational characteristics of a 60 kA plasma focus between 1 Hz and 10 Hz

Alameda Applied Sciences Corporation has already demonstrated a 1 Hz, ~4E5 neutron per shot plasma focus operating at 60 kA with 100 J stored. The source was upgraded with thermal management and a refractory anode to allow 10 Hz operation for extended periods without excessive erosion of the anode. The neutron yield variation was examined at repetition rates from 1 Hz to 10 Hz. The implosion time was observed to decrease with increasing repetition rate for a fixed fill pressure. The reduction in implosion time is attributed to an increase in anode temperature. Anode erosion, cathode erosion and insulator lifetime will be discussed. Gas lifetime is discussed in the context of single gas charge operation. Impurities in the gas were examined using optical emission spectroscopy.