The DC corona discharges in flowing dry and humid carbon dioxide

We report the results of an experimental study of the role of humidity in a DC corona discharge fed by carbon dioxide. The discharge is studied as a function of both positive and negative polarity. The formation of water clusters is suggested as playing a key role in the electrical characteristics in the discharge and the mobility of the measure ions. The formation of ozone is also shown to be important in characterising the properties of the corona discharges.