Surface streamer microwave discharge

An atmospheric-pressure pulsed microwave discharge on the surface of an insulating plate and between two insulating films is considered. The discharge is initiated in a quasi-optical microwave beam away from the beam-forming elements. The TEM field of the beam is less than the critical breakdown value. The initiator is a metallic dipole placed either directly on the plate surface facing away from the radiation source or between the films. The discharge has the form of branching streamer channels adjacent to the surface and filling up the cross section of the microwave beam with a field level higher than the value separating the subcritical and highly subcritical forms of the microwave streamer discharge. (C) 2002 MAIK "Nauka/Interperiodica".