Corona discharge of a vibrated insulating box with granular medium

Abstract Corona discharges are luminous signs of strong local electric fields allowing a continuous discharge into the surrounding atmosphere. They commonly occur at ends conductors high voltage. Here we report observation faint glow an insulating cm-sized box filled with mm-sized basalt beads. At ambient pressure in mbar range two light bands as soon and only if is vibrated it granular medium. In addition, also occurs inside box. We measured periodic outside spatial peaks positions bands. The period correlates to vibration frequency. These observations imply alternating beyond atmospheric breakdown, which generated emerge can be explained by tribocharging displacement charges between grains walls