Speaker
Shima Shimizu
(Kobe University (JP))
Description
The immense rate of proton-proton collisions at the Large Hadron
Collider (LHC) must be reduced from the nominal bunch-crossing rate of
40 MHz to approximately 1 kHz before the data can be written on disk
offline. The ATLAS Trigger System performs real-time selection of
these events in order to achieve this reduction. Dedicated selection
of events containing jets is uniquely challenging at a hadron collider
where nearly every event contains significant hadronic energy.
Following the very successful first LHC run from 2010 to 2012, the
ATLAS Trigger was much improved, including a new hardware topological
module and a restructured High Level Trigger system, merging two
previous software-based processing levels. This allowed the
optimization of resources and a much greater re-use of the precise but
costly offline software base. After summarising the overall
performance of the jet trigger during the first LHC run, the software
design choices and use of the topological module will be reviewed. The
expected performance of jet trigger for the second LHC run, to start
in 2015, will be described together with the available commissioning
measurements from early data taking.
Author
Shima Shimizu
(Kobe University (JP))
