The time correlation between two independent detector units was analysed. The two detectors were stagged above one another such that muons arriving at a sufficiently steep angle traversed both of them. The time difference of the recorded events plotted against the overall unix timestamp which is shown below reveals that the time difference is stable over several days.

A projection onto the ordinate axis indicates a time difference distribution which is Gaussian-shaped.

The sigma of the Gaussian is approximately 50 ns.