1. MOORE MOORE (Muon Object Oriented REconstruction) Track reconstruction in the Muon Spectrometer MuonIdentification MuonIdentification Reconstruction and Identification of Muons Divided in two components : MuidStandAlone: MuidStandAlone:   Extrapolation of tracks reconstructed by MOORE to the interaction point. MuidComb: MuidComb:   Combination of tracks reconstructed inside the Muon Spectrometer with tracks reconstructed in the Inner Detector TrigMoore: Implementation of MOORE/MuID in the framework of High Level Trigger at the Event Filter stage. Wrapped Strategy- Allows to execute the offline reconstruction chain from the online environment, reconstructing the event by accessing at all the Spectrometer data. The implemented chain is composed by Moore and MuidStandAlone. Seeded Strategy – Uses the hypotesys formed at the previous stage in the trigger process, accessing only to subdetectors data that are of interest for the selected trigger regions. (By now only regions selected by the LVL1 trigger have been used).

2. Moore in HLT- a contact point between offline and online. Wrapped, Full event Reconstruction Seeded: Access only the RoI from the LVL1 p T (GeV/c) (msec) rms (msec) (msec) rms (msec) 873306830 2059155821 5061195825 10061756426 30075236432 Atlas pcatr machine (2.4GHz) Atlas pcatr machine (2.4GHz) OPT build OPT build Timing package: TrigTools/TrigTime Timing package: TrigTools/TrigTime Strategies Seeded/wrapped Strategies Seeded/wrapped Conservative approach (i.e. data access and data preparation are included) Main ideas The algorithms operating in the High Level Trigger at the Event Filter stage should not operate only in a general purpose mode (reconstructing the event in full scan) but should be able to operate starting from hypothesys formed in the previous stages of the triggering process. Avoid the code duplication! Only the seeding has an ``ad hoc’’ implementation for the online environment. DC1 single Muons execution times In the table the average and rms is calculated on the events left after rejecting 5% of the events included in the high execution time tail In the table the average and rms is calculated on the events left after rejecting 5% of the events included in the high execution time tail

3. Wrapped strategy |  | < 1.05 Efficiency for the reconstruction of single Muons sample in wrapped strategy (event scan). This is equivalent to the execution of the offline version of the code. The analysis has been restricted to the barrel region. Resolution in wrapped and seeded strategy. Strategy seeded |  | < 1.05 Strategy wrapped |  | < 1.05

4. List of related papers ATLAS notes for more information: Moore as Event Filter in the ATLAS High Level Trigger ATL-SOFT-2003-008, ATL-DAQ-2003-020 Track reconstruction in the ATLAS Muon Spectrometer with MOORE ATL-SOFT-2003-007