Small Gap Experiments in Magnetically Insulated Transmission Lines

We have performed experiments using magnetically insulated transmission. lines (MITL´s) with anode-cathode gaps ranging from 0.15 to 0.40 cm. We have studied cathode plasma formation using laser schlieren photography, time resolved visible photography, and visible spectroscopy. Cathode plasma formation occurs within 10 ns of the application of the voltage pulse. Densities of 1015 cm-3-1017 cm-3 are inferred from the schlieren measurements. Negative ion formation in MITL´s has also been observed which may result in losses in high-current-density small-gap power feeds.