ATLAS Online Trigger Rate Monitoring System [TDAQ]

At the ATLAS Experiment, a two-level trigger system reduces the LHC’s bunch-crossing rate of 40 MHz to an average recording rate of 1 kHz. Xmon is a subsystem that compares recorded trigger rates to predicted values based on the beam’s luminosity. The predictions are calculated using data from past runs to parameterize the luminosity dependence of the event rate for each trigger algorithm. We present an overview of Xmon operations and a redeveloped website to display Xmon datasets.