Speaker
Martin purschke
Description
The PHENIX experiment consists of many different detectors and
detector types, each one with its own needs concerning the
monitoring of the data quality and the calibration. To ease the task
for the shift crew to monitor the performance and status of each
subsystem in PHENIX we developed a general client server based
framework which delivers events at a rate in excess of 100Hz.
This model was chosen to minimize the possibility of accidental
interference with the monitoring tasks themselves. The user only
interacts with the client which can be restarted any time without
loss or alteration of information on the server side. It also
enables multiple people to check simultaneously the same detector -
if need be even from remote locations. The information is
transferred in form of histograms which are processed by the client.
These histograms are saved for each run and some html output is
generated which is used later on to remove problematic runs from the
offline analysis. An additional interface to a data base is provide
to enable the display of long term trends.
This framework was augmented to perform an immediate calibration
pass and a quick reconstruction of rare signals in the counting
house. This is achieved by filtering out interesting triggers and
processing them on a local Linux cluster. That enabled PHENIX to
e.g. keep track of the number of J/Psi's which could be expected
while still taking data.
Author
C. Pinkenburg
(BROOKHAVEN NATIONAL LABORATORY)
