Whether and how the vapors of Al, Cu, Fe, and W influence the dynamics of apokamps

Abstract

Abstract The recent hypothesis about the initiation of red sprites in the Earth atmosphere in presence of metal atoms was verified. We have tested this hypothesis using Al, Cu, Fe, and W electrodes in laboratory apokamp discharges in air at a pressure of 45 and 760 Torr. Our experiments show that the electrode material does influence the apokamp dynamics. However, for Fe and W, compared to Al and Cu, the start voltage of an apokamp in pulse-repetition mode is higher and its length is shorter. The emission spectrum of apokamp discharges reveals lines of their metal electrodes. Thus, the experiments confirm the hypothesis on the contribution of metal vapors from burnt meteors to the initiation of red sprites in the Earth atmosphere.