Nanosecond Pulsed Discharge Phenomenology in Micrometer-Sized Radially Confined Air Gap

Geometry effects on nanosecond-scale pulsed corona discharges propagating in rectangular glass tubes are reported in this paper. Both the section and thickness of the tubes are the parameters which are used to investigate the discharge phenomenology. Three picosecond high-speed ICCD cameras are used to derive the propagation velocities from a single discharge event. Propagation is significantly speeded up in radially highly confined gaps and promoted close to edges. Inception of weak discharges along the tubes can be observed.