Analysis of the relationship between light intensity and electrical power of corona discharges

Abstract This work analyzes the intensity of the light emitted by corona discharges using a smartphone camera, which is compared to the electrical power associated with the corona discharges. The raw images from the camera provide essential information for the experiment. Data at different atmospheric pressures are also provided to help students understand that at lower pressures, due to the increased mean free path of the electrons, they are more efficient at ionizing neutral air molecules. An analysis of the data obtained also makes it possible to estimate the values of the energy of the electrons involved in the discharge process, the mean free path of the electrons and the cross section for electron collision, using much simpler equipment compared to other studies. The data and approach presented in this paper can be adapted for a group project or a guided practical session for both undergraduate and graduate courses.