A simple device of generating glow discharge plasma in atmospheric pressure argon

Atmospheric pressure glow discharge is realized in argon by using a plasma needle. With increasing the applied voltage, uniform plasma increases in scale from a small region near the needle tip to a plasma plume with a length of about 20 mm. The discharge mechanism is discussed based on the light emission waveforms from the plasma. Optical emission spectroscopy is used to determine excited electron temperature and vibrational temperature, and the results indicate that the excited electron temperature and the molecular vibrational temperature are about 6000 and 2300 K, respectively. (C) 2007 American Institute of Physics.