Trigger Upgrades Introduction and International Perspective

1. Trigger UpgradesIntroduction and International Perspective Norman Gee ATLAS-UK Upgrade Annual Review RAL 10-May-2011

2. Overview • Trigger in ATLAS • ATLAS TDAQ Management Structure • TDAQ R&D for Upgrade • General Comments

4. Trigger & Data Acquisition - TDAQ • Treated in ATLAS like another detector system • Possibly the largest - 74/174 institutes • Responsibilities • Level-1 Trigger • High-Level Trigger = Level-2 + Event Filter • DAQ: Data collection, movement, recording • Includes ATLAS control room • Detector Control System (voltages, ...) • ATLAS TDAQ management • Trigger/DAQ Management Team - TDMT • Trigger PL & DAQ PL, alternate on ATLAS EB • TDAQ Steering Group • TDAQ Institute Board • For upgrade: “TDMT+3” • N Gee, N Konstantinides, S Demers (Yale)

5. TDAQ Steering Group • TDMT • LVL1 • L1Calo; L1Muon (Barrel and Endcap); Central Trigger Processor • HLT/DAQ • DAQ/HLT Coordinators • Trigger • Includes John Baines (Trigger Coordination Group) • TDAQ Upgrade • Norman Gee , Nikos Konstantinidis (“TDMT+3” ) • Ex-officio • TDIB Chair , Resources coordinator, other ATLAS areas • Atlas management – deputy spokesman normally attends

6. Context of TDAQ Upgrade R&D • 21 upgrade activities already approved by (previous) USG in ATLAS • Many have TDAQ implications. Key ones for TDAQ are • Inner Detector (relationship to L1 track trigger); • Muon Spectrometer and Electronics (relationship to L1 muon trigger); • FTK – Hardware Track Finder (a TDAQ project; relationship to HLT); • LAr and Tile Calorimeter electronics (relationship to L1 calo trigger) • TDAQ (covers all TDAQ upgrades in Phases I and II) • All ATLAS-UK Trigger Upgrade work is included here • Two key documents expected within the next 6 months • Level-1 Trigger Technical Proposal • Covers Phase I + Phase II (in less detail). S Hillier chairs ed board, +3 UK • ATLAS Upgrade LoI • Also covers all upgrade phases. N Gee ed board for TDAQ

7. Context evolution since original ATLAS-UK Upgrade Bid • FTK (fast tracker) project approved to proceed to TDR stage • Requires simulation from HLT to show benefits; • Availability of tracks at HLT input implies evolution in HLT strategy • Preferred L1Track trigger uses ”seeds” from calo and muon triggers • Implies two-level L0A/L1A hardware trigger, L0A (to provide seeds) and L1A (using L1Track information to read out full detector) – details to be worked through with all detectors • LAr and Tile calorimeters propose pilot test of on-detector digitisation • A Trigger slice was already proposed in UK, but now L1Calo/Lar/Tilecal need to work on common timetable for tests • L1Muon Trigger – latency issues • Trigger latency studies initially to look at Phase I L1A trigger latency with topo processor reveal various problems for muon detectors – Phase II trigger architecture is needed to design Phase I electronics

8. Comments - Conclusions • TDAQ is treated like a detector – but not quite • TDAQ is normally expected to provide a service for testing even during beam down time, and even while upgrades are underway on the TDAQ system itself; full TDAQ down time is very hard to schedule • Many changes are applied incrementally – e.g. the recent addition of the Missing-ET significance trigger. Some institutes regard these as M&O, some as upgrade • Scheduling of trigger upgrades has to match detector upgrades, not only the LHC Luminosity plan • Trigger upgrades provide benefit from the day they are installed