Speaker
Andrea Messina
(Conseil Europeen Recherche Nucl. (CERN)-Unknown-Unknown)
Description
The ATLAS Level-1 Central Trigger (L1CT) consists of the Central Trigger
Process (CTP) and the Muon to Central Trigger Processor Interface
(MuCTPI). The CTP forms the final Level-1 Accept (L1A) decision based
on the information received from the Level-1 Calorimeter Trigger system
and from the muon trigger system through the MuCTPI. Additional inputs
are provided for the forward detectors, the filled-bunch trigger, and
the minimum-bias trigger scintillators.
The CTP also receives timing signals from the LHC machine. It fans out
the L1A together with timing and control signals to the Local Trigger
Processor (LTP) of the sub-detectors. Via the same connections it
receives the Busy signal to throttle the Level-1 generation. Upon
generation of L1A the L1CT sends trigger summary information to the DAQ
and Region-of-Interest to the Level-2 Trigger system.
In this contribution we will present an overview of the final L1CT
trigger system as it is now installed in the ATLAS experiment and we
will describe the current commissioning and integration activity at the
experimental site. The system is now continuously used during cosmic-ray
runs to exercise the full trigger chain and read-out of sub- detectors.
These test are bridging the experiment towards the commissioning phase
with protons in the LHC as it is foreseen for this summer. We will
discuss in particular the results achieved in operating the system with
cosmic-rays and, possibly, the commissioning results with the first
proton events in the LHC.
Primary author
Andrea Messina
(Conseil Europeen Recherche Nucl. (CERN)-Unknown-Unknown)
