Decrease of the air breakdown threshold by the subcritical streamer discharge when the initiator is placed near the metal screen

The influence of the screen size on the air breakdown by an induced subcritical streamer discharge is discussed based on the data of physical and computational experiments. A cylindrical metal vibrator mounted at a certain distance from the screen is used to initiate a streamer discharge. The initiator length is comparable with the half wavelength of electromagnetic field. Data on the effect of the distance from the emitting aperture to the screen and its width on the breakdown pressure are given. The dependence of the field amplification factor at the poles of a linear vibrator on the size of the reflector screen is obtained. Keywords: breakdown, streamer discharge, microwave discharge, plasma-assisted combustion.