We study the origin of filamentary patterns in a sinusoidally driven surface barrier discharge at high over-voltage in atmospheric pressure air. Using a time-correlated single-photon counting based optical emission spectroscopy, we reveal ultrafast processes within generated discharges in both polarities of the applied voltage. For negative polarity, we observe initiation of complex streamer cascade which emerges far from the bare cathode. This event is responsible for long filamentary structure detected by an intensified CCD camera and transfers an exceptionally large electrical charge. It constitutes another, previously unknown, mechanism contributing to the charge-transfer equilibrium in studied periodical discharge. The revealed process leads to the formation of an intense cathode spot, a critical condition for plasma-transition into a highly ionised state.

我们研究了大气压空气中高过电压下正弦驱动表面势垒放电中丝状图案的起源。使用基于时间相关单光子计数的光发射光谱，我们揭示了在施加电压的两种极性下产生的放电中的超快过程。对于负极性，我们观察到远离裸阴极出现的复杂流注级联的启动。该事件是由增强型 CCD 相机检测到的长丝状结构的原因，并传输异常大的电荷。它构成了另一种以前未知的机制，有助于研究周期性放电中的电荷转移平衡。揭示的过程导致形成强烈的阴极斑点，