Monitoring of the Trigger Timing of the ATLAS Level-1 Trigger

The Level-1 trigger is the first trigger stage of the ATLAS detector. It is a two stage trigger system (in run II) to select the collision events that should be recorded. The $1^{st}$ stage is custom made electronics and should reduce the event rate from 40MHz to 100kHz due to the fact that this is the maximal readout rate for the tracking systems. It is an important task to monitor the trigger timing and find a potential shift in the timing quickly.