Spectroscopic composition of Corona Discharge and some effects on materials

Corona-discharge CD is just the point at which the air breakdown begins to happen. This phenomenon is usually present when high voltage is applied between a needle and a metallic plate. The air molecules begin to ionizate, separation of their positive and negative charges occur and any minimum voltage increment produces a suddenly discharge between the electrodes. At this critical non-equilibrium point, some of the opposite separated charges are recombined and a light violet-blue emission is produced at the tip of the needle. The released energy can cause some kind of chemical transformation on the materials nearby. In this work we reported the composition of this emission captured from tip of the needle. We show the kind of change that this Corona-discharge produced on fabrics of cotton and linen. CD has been considered as one of the most probably effect that generate the image in the so called Turin Shroud. We present some image produced by controlled CD. Some discussion is given.