The Fast Monitoring is an important component of the DIRC monitoring. Parallel to the data taking in IR2, the status of the different components of BaBar (subdetectors, L1 and L3 triggers, dataflow, Trickle Injection system) are monitored through the Fast Monitoring system which has two main components.

• The real-time monitoring which is the responsability of the DQM who is looking at a set of component-dependent histograms through a JAS interface. The histograms (for the DIRC, various occupancy and timing plots plus a summary of the online errors) are accumulating data over the current run and cleared at the startup of a new run.
  The corresponding DIRC packages are DrcOfm and DrcMonTools.
• In addition to the histograms displayed on the DQM JAS pages, several other histograms are filled during the run and then written in an hbook file located in a directory whose generic name is
  /nfs/bbr-srv02/u4/Monitoring/OutputArchive/YYYY/MM/LiveFastMon.
  The hbook names are generated using the following convention:
  LiveFastMon-00<run number>-YYYYMMDD-<time>.hbook where <time> is the time at which the fast monitoring starts to accumulate data (usually at most 1-2 minutes after the beginning of the run).
  Once the LiveFastMon stream has been created, an automatic post-processing starts and analyzes in particular the DIRC histograms (through the package DrcOfmPostProcess). The output of this job is a postscript file which must be checked offline by the DIRC oncall-expert to make sure that nothing has been missed by the shifters.
  Checking all such files is a mandatory task of the DIRC oncall expert.

The table below provides the main links related to the DIRC Fast Monitoring.