HiSPARC is an extensive network of cosmic ray detection stations mainly across The Netherlands and United Kingdom. Its primary goal is to analyse cosmic ray air showers by sampling their footprints using multiple detectors. Also the detection rates per single detector are recorded. These 'singles rates’ fluctuate in time. Large fluctuations are caused by precipitation. During rain an excess of ²²²Rn daughter nuclei, scavenged by raindrops, falls to the ground. This results in an increase in the number of gamma rays from the decay of ²¹⁴Bi. The excess of events can be described by a simple decay model that takes fluctuations of the rain intensity into account.

HiSPARC 是一个广泛的宇宙射线探测站网络，主要分布在荷兰和英国。它的主要目标是通过使用多个探测器对其足迹进行采样来分析宇宙射线空气簇射。还记录了每个检测器的检测率。这些“单身率”随时间波动。大的波动是由降水引起的。在下雨期间，被雨滴清除的²²² Rn 子核会落到地面上。这导致来自²¹⁴ Bi衰变的伽马射线数量增加。事件的过量可以通过一个简单的衰减模型来描述，该模型考虑了降雨强度的波动。