1. Atlas ACAT2000 Batavia, IL, USA 16-20 October 2000 More Performance and Implementation of an Object Oriented Track Reconstruction Model in Different OO Environments

2. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 2 ACAT2000 Batavia, IL, USA 16-20 October 2000 Outline Overview of LHC, CMS and Atlas Review of the OO track reconstruction model Previous Implementation of the OO model into CMS ORCA and two Atlas LVL-2 trigger SW environments New performance result Implementation of the OO model into the new Atlas OO offline framework Athena Summary and prospects

3. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 3 ACAT2000 Batavia, IL, USA 16-20 October 2000 L H C

4. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 4 ACAT2000 Batavia, IL, USA 16-20 October 2000 CMS and ATLAS CMS

5. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 5 ACAT2000 Batavia, IL, USA 16-20 October 2000 Trackers of CMS and Atlas CMS ATLAS

6. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 6 ACAT2000 Batavia, IL, USA 16-20 October 2000 OO Tracker Model (I) Brief history -- Was originally designed by Irwin GAINES and Sijin QIAN for CMS offline software (3/1995) -- Preliminarily integrated into ORCA (8-9/1999) -- 1998~1999, was implemented into Atlas LVL-2 trigger OO reference software framework -- 8~11/1999, was implemented into LVL-2 Ctrig framework, which produces ntuples for trigger performance study ===> Atlas Trig/DAQ Technical Proposal (4/2000) -- 27/8/2000, was preliminarily implemented in Athena -- was reported at CHEP’97, ‘98, ‘2000 and AINHEP’99,...

7. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 7 ACAT2000 Batavia, IL, USA 16-20 October 2000 OO Tracker Model (II) Main ingredients of the OO model: –Problem statement ==> class diagram –Function statement ==> object diagrams and message trace diagrams Main features of the model: –Use well known HEP concepts for classes –Extensive use of Standard Template Library (STL), in both model design and C++ coding –Initially successful re-use of FORTRAN legacy code (for Kalman filtering method) in the member functions of various classes; later converted them to C++ in a straightforward manner; now pure C++ –Flexible enough to be re-used in multiple HEP experiments (only implementation of layer class is different)

8. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 8 ACAT2000 Batavia, IL, USA 16-20 October 2000 The latest version of class diagram

9. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 9 ACAT2000 Batavia, IL, USA 16-20 October 2000 Object Diagrams First scenario Second scenario

10. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 10 ACAT2000 Batavia, IL, USA 16-20 October 2000 CMS Implementation Uses first scenario (internal hit triplets as seeds) Conceptual structure of “mytest.cpp” in the ORCA example directory –RecHit objects (in ORCA) are converted to “hit” object of the OO model. –Layer objects of OO model are instantiated with hard-wired code at this stage, can be done from ORCA tracker geometry in future. –All classes in the OO KF tracking model are brought in straightforwardly without any major change.

11. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 11 ACAT2000 Batavia, IL, USA 16-20 October 2000 Conceptual structure of “mytest.cxx” in ORCA example directory

12. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 12 ACAT2000 Batavia, IL, USA 16-20 October 2000 Previous Atlas Implementation LVL-2 trigger requirement (O(10ms) time slot) ==> execution time is a factor of concern. – use 2nd scenario (outside seeds) – work in Region of Interest (RoI) instead of in full  -  range Frameworks – LVL-2 Reference Software System (OO designed, input ASCII data) – Ctrig (input from ASCII files, produce ntuples, etc.) Seed modes: (1) TRT guided (inward pattern recognition) (2) pixel guided (outward pattern recognition) Tracking corrections: (1) Multiple scattering (yes); (2) Energy loss (yes for electrons); (3) Non-uniform B field (in near future).

13. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 13 ACAT2000 Batavia, IL, USA 16-20 October 2000 Energy Loss Correction   (1/Pt) distribution (1/GeV) 1 GeV5 GeV 20 GeV electrons electrons electrons

14. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 14 ACAT2000 Batavia, IL, USA 16-20 October 2000 Performance –Execution speed (on 600 MHz AMD Athlon, under Linux) B-physics (at low lumi.) TRT seeded Pixel seeded P T min (GeV/c) No. of seed Time(ms) No. of seed Time(ms) 0.5 /event /event 1.0 /event /event – Memory usage is in O(10 MB), depends on data volume – Efficiencies (single track events, B-physics events), Resolutions (momentum, impact parameter, etc.) – B-physics study in the channel B -->  – Many more latest results are at (1) "Atlas Trig/DAQ Technical Proposal" (CERN/LHCC/2000-17) http://atlasinfo.cern.ch/Atlas/GROUPS/DAQTRIG/SG/TP/draft_tp.html (2) ATL-DAQ-2000-031 (6/2000) http://documents.cern.ch/cgi-bin/setlink?base=atlnot&categ=Note&id=daq-2000-031 (3) http://www.usatlas.bnl.gov/~sijin/oo.html

15. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 15 ACAT2000 Batavia, IL, USA 16-20 October 2000 B-physics mass reconstruction Reconstruction of B -->  mass hypothesis in ATLAS Level-2 trigger using the Kalman filtering method

16. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 16 ACAT2000 Batavia, IL, USA 16-20 October 2000 Implementation in Athena Once per runOnce per event Loop over seeds T ransient D ata S tore Geome- trical data SCT-Kalman Layers Digi Seeds Seed source Space ponits Recon- structed tracks Space point builder Seed builder Layer builder

17. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 17 ACAT2000 Batavia, IL, USA 16-20 October 2000 Athena Run Log File (1) ApplicationMgr DEBUG Creating Top Algorithm RunKF ApplicationMgr INFO Application Manager Configured successfully ChronoStatSvc INFO Service initialized successfully EventDataSvc INFO Service initialized successfully EventPersistenc... INFO Service initialized successfully EventPersistenc... INFO Added successfully Conversion service:ZebraTDRCnvSvc. ParticlePropert... DEBUG StdHepID Map size =201 ZebraTDRCnvSvc INFO Service initialized successfully ApplicationMgr INFO Detector description not requested to be loaded EventSelector INFO Service initialized successfully RunKF INFO initialize() in RunKF ApplicationMgr INFO Application Manager Initialized successfully RunKF INFO execute() in RunKF RunKF INFO Got event. execute in KFEventLoader Space points inputted ================== total # of hits: 11 rfz (0): 51.57, error: 10.00 rfz (1): 0.37, error: 2.00 rfz (2): 82.62, error: 0.00 section: 7 hit-id: 1200010

18. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 18 ACAT2000 Batavia, IL, USA 16-20 October 2000 Athena Run Log File (2) ------------------------------------------ rfz (0): 50.40, error: 10.00 rfz (1): 0.37, error: 2.00 rfz (2): 82.62, error: 0.00 section: 7 hit-id: 1200020 ------------------------------------------ rfz (0): 52.79, error: 10.00 rfz (1): 0.37, error: 2.00 rfz (2): 82.62, error: 0.00 section: 7 hit-id: 1200030 ------------------------------------------- rfz (0): 51.57, error: 10.00 rfz (1): 0.37, error: 2.00 rfz (2): 82.62, error: 0.00 section: 7 hit-id: 1200040 ---------------------------------------------. Seed created ============ nhseed: 3 parameter(0-4): 29.74 0.37 45.08 0.53 -0.01 1/pt = -0.04

19. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 19 ACAT2000 Batavia, IL, USA 16-20 October 2000 Athena Run Log File (3) Recontructed trackes (1) ==================== Track parameters: 92.500, 53.290, 20.698, 0.524, 0.363, -0.000, 1 Weight matrix: 37198.793 -96615.164, 251010.844 -380.575, -147.010, 20536.547 1997824.125, -5181015.000, 52.231, 120808296.000 -21384064.000, 55373708.000, -613.444, -1414695040.000, 17693335552.000 Hit list on the track: track::show : 1200040 51.57 0.37 82.62 0.00 track::show : 1300010 53.84 0.43 91.62 0.00 track::show : hit id:1200040 1300010 Seed ID = 1 Chi2 = 3.1 Missing points = 0 Hit Chi2 contribution: hit dchi2 (1): 0.00 hit dchi2 (2): 2.95 Recontructed trackes (2) ==================== …..

20. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 20 ACAT2000 Batavia, IL, USA 16-20 October 2000 Lessons Learned C++’s new features (for previous Fortran programmers) now can be handled by some powerful debugging tools, e.g. –“INSURE++” to detect the memory leaks –“DDD” graphic debugger to detect the pointer bugs Integration of an OO model into a general OO environment of whole experiment needs a stable framework with a stable interface. As soon as all functionality of I/O objects needed by the model are available, the integration is straightforward.

21. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 21 ACAT2000 Batavia, IL, USA 16-20 October 2000 Conclusions OO makes it easier to do cooperative development among widely separated collaborators (promotes truly modular designs) OO makes re-use easier: the implementation of this OO model into several frameworks of two LHC experiments demonstrates -- the implementation structure is very similar for different experiments -- the experience in code development can be shared among different experiments immediately

22. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 22 ACAT2000 Batavia, IL, USA 16-20 October 2000 Summary and Prospects We are moving towards a realistic OO track reconstruction model for HEP experiments –the memory usage of this OO model is moderate –the track finding efficiency is satisfactory –the execution speed is approaching the LVL-2 trigger requirement It can be used in different experiments and frameworks with only minor modifications

23. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 23 ACAT2000 Batavia, IL, USA 16-20 October 2000 Ongoing Works for Athena Space points input (add correct errors) Complete the package decomposition Set more properties in various modules to replace the hardwired things Aim for the near future: to re-produce the Atlas Trig/DAQ TP result and beyond To test more modes for Space-points-builder and Seed-builder To implement the non-uniform B-field correction

24. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 24 ACAT2000 Batavia, IL, USA 16-20 October 2000 Efficiencies for  and e muons electrons

25. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 25 ACAT2000 Batavia, IL, USA 16-20 October 2000 Efficiencies for B-physics (1)  vs. Pt  for e from B0 --> J/   vs. 

26. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 26 ACAT2000 Batavia, IL, USA 16-20 October 2000 Efficiencies for B-physics (2)  vs. Pt  for e from B0 -->   vs. 

27. CMS & Atlas Atlas OO Tracker Model Implementation S. Qian 27 ACAT2000 Batavia, IL, USA 16-20 October 2000 Resolutions  Pt 20 GeV  (tops: barrel; bottoms: endcap) D 0