1. Early 2008 Marc-Andre Dufour (McGill) was the trigger rates group (developed Trigger Rates Tool) later replace by Miika Klemetti Early 2008 Bilge Demirkoz (CERN) joined effort (brings trigger menu expertise) March 2008 Andrew Brandt (UTA) charged with leading trigger rates effort by Srini; Arnab Pal (UTA) joins (runs BNL rate jobs) May 2008 Seth Caughron (Columbia) joins to work on enhanced bias approach Edward S-G (UTA) taking over responsibility for rate runs, developing higher luminosity rate measurements Elliot Lipeles +Rustem Ospanov (Penn) join in 2009 Summer 2009 Josh Kunkle (Penn) jojins Summer 2010 SMU joins Steve Sekula+Aidan Sean Randle-Conde Monica Dunford (CERN) joins, Elliot becomes unofficial co-leader 1 Trigger Rates Group 11/9/2010UTA DOE Review Andrew Brandt (UT-Arlington)

2. Trigger Rates Pre-March 2010 Initial charge: determining the rates of triggers and trigger menus, as new versions of the trigger software are released, and new triggers are developed. Measured and compared Monte Carlo rates for different versions of event generators and detector simulation, different beam energies, different software releases, and datasets with varying levels of pileup. We developed post-processing scripts which allow easy comparison of trigger versions and provides summaries by trigger groups, to maximize the usefulness of the trigger rates measurements for ATLAS trigger experts as well as general collaborators. Results are then posted on an ATLAS web page The combination of new triggers, changing prescale factors, calibration changes, and various bugs, combined with frequent menu and software changes, clearly makes the Rates group's job important, interesting, and challenging. 11/9/2010UTA DOE Review2

3. 11/9/2010UTA DOE Review3 Trigger Rates Post-March 2010

4. 11/9/2010UTA DOE Review4 Trigger Rate Calculations

5. 11/9/2010UTA DOE Review5 Data Predictions: Extrapolated from Low Lum (2.6 E30) Compared to High Lum Corrected for pile-up non-linearities based on number of vertices

6. MC vs. Data Rates (Calorimeter Triggers) 11/9/2010UTA DOE Review6 Discrepancy existed in 900 GeV data as well; we traced to MC tune dependence

7. 11/9/2010UTA DOE Review7 MC vs. Data Prediction

8. Further Evidence for Tune Dependence 11/9/2010UTA DOE Review8

9. Discrepancy for Muons (especially at low momentum) 11/9/2010UTA DOE Review9

10. Summary Trigger Rates Group has provided a critical service to ATLAS Post standardized rates, work with MC developers, trigger experts, online, menu group A key contribution to ATLAS operations and physics through menu development (6 orders of magnitude increase in 8 months!) and bandwidth allocation https://twiki.cern.ch/twiki/bin/viewauth/Atlas/AtlasTriggerRates 11/9/2010UTA DOE Review10

11. Plans in Flux In the process of resigning from group leadership Would like to work on long term predictions 10 33 and above Correlated with AFP, DØ Higgs, personnel 11/9/2010UTA DOE Review11