Solar flares release high amounts of energy into the solar system and can negatively impact earth based systems through their effects on satellites and power systems. It is hence important to understand and forecast their occurrence. The solar flare waiting time distribution (WTD) defines the amount of time which elapses between the occurrence of successive flares and hence provides a starting point for forecasts and risk assessment. Previous research has hypothesized that the observed WTD can be derived from a simple model which posits that flares follow a nonstationary Poisson process. This Poissonian assumption has implications for fundamental physical theories about the origin of flares, since it is a direct consequence of the widely studied avalanche model. However in this paper we call the Poissonian assumption into question, by showing that the occurrence of solar flares seems to have a substantial amount of burstiness and self-excitation that continues to exist even when controlling for the solar cycle. This leads to a strong non-Poissonian dependence between the occurrence time of successive flares.

太阳耀斑向太阳系释放大量能量，并可能通过其对卫星和电力系统的影响而对基于地球的系统产生负面影响。因此，重要的是了解和预测它们的发生。太阳耀斑等待时间分布（WTD）定义了连续耀斑发生之间的时间量，因此为预测和风险评估提供了起点。先前的研究假设观察到的WTD可以从一个简单的模型得出，该模型假定耀斑遵循非平稳的Poisson过程。这种泊松假设对火炬起源的基本物理理论具有影响，因为它是被广泛研究的雪崩模型的直接结果。但是，在本文中，我们对泊松假设进行了质疑，通过证明太阳耀斑的发生似乎具有大量的爆发性和自激性，即使在控制太阳周期时也继续存在。这导致了连续爆发的发生时间之间强烈的非泊松依赖性。