Figure 12.
Event selection in serial X-ray diffraction experiments, borrowing from terminology used in particle physics experiments. Level-1 veto uses external diagnostics to determine whether a sample has been intersected by the X-ray pulse, while Level-2 vetoing relies on readout of only a portion of the detector. Level-3 event filters work in parallel, performing rapid analysis of the entire detector data to determine whether a particular event is worthy of retention for further analysis. Cheetah currently performs the role of a Level-3 event filter in addition to performing data reduction tasks.