Online Monitoring of the Pierre Auger Observatory

The data taking of the different components of the Pierre Auger Observatory, i.e. the surface detectors (SD) and the fluorescence telescopes (FD) has to be supervised by a shift crew on site to guarantee a smooth operation. A monitoring tool has been developed to support the shifter in judging and supervising the status of the detector components, the electronics and the data-acquisition (DAQ). Data are collected online for this purpose in the regular measuring time as well as in dedicated modes e.g., for calibration or atmospheric surveys. While for some components like SD this information is directly transmitted to the DAQ on the central campus, for others it is stored in a database locally, e.g for FD within the four remote housings of the telescopes. These databases are replicated to the central server on the campus via a wireless long distance link. A web-interface implemented on a dedicated server can dynamically generate graphs and particular developed visualisations to be accessible not only for the shifter, but also for experts remotely from anywhere in the world. In addition, in case of special occurrences an alarm is triggered automatically. This tool does also offer a unique opportunity to monitor the long term stability of some key quantities and the data quality. The concept and its implementation will be presented.