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Transition from Interpulse to Afterglow
Plasmas
Introduction
In the power-off phase, plasmas generated by repetitive short-pulse micro-
waves in a multicusp (MC) magnetic eld show a transitive nature from
interpulse to afterglow as a function of pulse duration t
w
= 20–200 μs. The ion-
ized medium can be driven from a highly nonequilibrium to an equilibrium
state inside the pulses, thereby dictating the behavior of the plasma in the
power-off phase. Compared to afterglows, interpulse plasmas observed for
t
w
< 50 μs are characterized by a quasi-steady-state in electron density that
persists for ~20–40 μs even after the end of the pulse, and ...