Speaker
Dr
Jörg Stelzer
(CERN, Switzerland)
Description
The ATLAS detector at CERN's LHC will be exposed to proton-proton
collisions at a rate of 40 MHz. To reduce the data rate, only
potentially interesting events are selected by a three-level trigger
system. The first level is implemented in custom-made electronics,
reducing the data output rate to less than 100 kHz. The second and
third levels are software triggers with a final output rate of 100 to
200 Hz. A system has been designed and implemented that hosts and
records the configuration of all three trigger levels at a centrally
maintained location. This system provides consistent configuration
information to the online trigger for the purpose of data taking as
well as to the offline trigger simulation. The use of relational
database technology provides a means of flexible information browsing,
easy information distribution across the ATLAS reconstruction sites,
and reliable recording of the trigger configuration history over the
lifetime of the experiment. The functionality of this design has been
demonstrated in dedicated configuration tests of the ATLAS level-1
Central Trigger and of a 600-node software trigger computing farm. We
present an overview of the main system components, including a
sophisticated, JAVA-based front end to populate and maintain the
configuration information, and report on the current status.
Primary authors
Dr
Andreas Hoecker
(CERN, Switzerland)
Dr
David Berge
(CERN, Switzerland)
Prof.
Johannes Haller
(Hamburg University, Germany)
Dr
Jörg Stelzer
(CERN, Switzerland)
Dr
Miroslav Nozicka
(DESY Hamburg, Germany)
Dr
Paul Bell
(Manchester University, UK)
Mr
Simon Head
(Manchester University, UK)
Dr
Thorsten Wengler
(Manchester University, UK)
