Formation of electrodeless double-headed streamers (DHS) at sub-breakdown conditions
Résumé
Recent decades have seen significant advancements in understanding sprites and ionization waves. However, the natural occurrence of double-headed streamers (DHS) after breakdown remains unexplained. Extensive modeling studies have been conducted, but no experimental validation has been achieved until now. This work introduces the first experimental model of DHS using a primary plasma jet device at ground pressure. The experiment involves a noble gas flow (Helium or Neon) mixing with ambient air. Advanced diagnostics, such as optical emission spectroscopy (OES) and the Stark effect, were used to measure the electric field along the discharge axis. The results show that DHS can ignite under sub-breakdown conditions, highlighting the importance of pre-ionization. These findings align with previous modeling studies and provide insights into fundamental processes in atmospheric electricity.