Torch Discharge

a high-frequency single-electrode gas discharge. At pressures of the order of or higher than atmospheric pressure, a torch discharge is similar to a candle flame in shape. As the pressure is reduced, a torch discharge loses its characteristic shape and becomes a discharge with a uniform diffuse glow. Torch discharges may occur at frequencies of the order of or higher than 10 megahertz and may be produced in various ways, for example, by removing one electrode of a high-frequency corona. As is the case with a corona discharge, a torch discharge is most easily triggered by electrodes with large curvature, such as points and thin conductors. The temperature of a torch discharge is different at different points and can be as high as 4000°K near the electrode.