After the first and second return strokes (RSs) of a multi-branch triggered lightning flash, the M component of two different initiation mechanisms burned: (1) Upward leader (UL)-M component, (2) Downward leader (DL)-M component. The UL-M component burned immediately after the RS (about 0.5 ms after the RS). At this time, an UL developing to the cloud generated outside the main channel of the continuous current (CC). With the development of the UL, the M component is formed in the CC channel. The obvious DL process can be observed during DL-M component. The speed of DL is about 2 × 10 m/s, when DL was intercepted by CC channel, M component will generate. The current peak and electric field peak of the UL-M component were larger than those of the DL-M component. It was worth noting that the M component formed by the UL slightly developing to the ground at the head of it did not produce an electric field change at the observation point 2 (1550 m horizontally from the rocket triggered lightning point), which was a result of the combined effect of the positive charge in the branch head and the negative charge in the main channel at the same height. The reflection phenomenon of the M component was also observed in a DL-M component process. The CC in the channel after the RS plays a key role in the formation of the M component. It forms the M component by intercepting the current wave transmitted to the ground from the cloud or the lightning branch.

中文翻译：

---

多支火箭中两种M组件触发闪电的新见解

在多分支触发闪电的第一次和第二次回击（RS）之后，两种不同引发机制的 M 组件被烧毁：（1）向上先导（UL）-M 组件，（2）向下先导（DL）- M 分量。 UL-M 组件在 RS 后立即烧毁（RS 后约 0.5 毫秒）。此时，在连续电流(CC)的主通道之外产生向云端发展的UL。随着UL的发展，CC通道中形成了M分量。在DL-M组件期间可以观察到明显的DL过程。 DL的速度约为2×10 m/s，当DL被CC信道截获时，会产生M分量。 UL-M组件的电流峰值和电场峰值均大于DL-M组件。值得注意的是，UL头部向地面轻微发展形成的M分量在观测点2（距离火箭触发闪电点水平1550 m处）并没有产生电场变化，这是由于同一高度分支头中的正电荷和主通道中的负电荷的综合效应。在DL-M组分工艺中也观察到了M组分的反射现象。 RS之后通道中的CC在M分量的形成中起着关键作用。它通过拦截从云层或雷电分支传输到地面的电流波形成M分量。