Electron flow through geometrical discontinuity in coaxial magnetically insulated transmission lines

Magnetically insulated transmission lines (MITLs) under high-power operatio n are dominated by space-charge current flowing between an anode and a cath ode. When MITLs have geometrical discontinuity, the interaction between the disturbed electrons and the nonlinearly coupled electromagnetic field make s their behavior difficult to predict. The results of particle simulation s how that the space-charge electrons tend to maintain the effective impedanc e of the transmission lines, by changing their distribution and the boundar y of the electron cloud. Although a fraction of the space-charge flow shunt s the gap at the discontinuity when the discontinuity is larger than a crit ical value, the total upstream current is still preserved. To discuss this impedance adjustment process and the critical value, we propose a laminar f low model with constant current density.