1. 11 November 2010 Rudi Frühwirth Physics algorithms and data analysis HEPHY Evaluation

2. Physics algorithms and data analysis 2Rudi Frühwirth11 November 20102Rudi Frühwirth Mission ► Participation in projects, with focus on –Event reconstruction software Pattern recognition for track and vertex finding Robust and adaptive estimation in track and vertex fitting –Detector related software Geometrical alignment, detector design and optimization –Physics analysis software and statistical consulting for analysis groups ► Generic developments –Methods and software tools that are of general interest to particle physics experiments

3. Physics algorithms and data analysis 3Rudi Frühwirth11 November 20103Rudi Frühwirth Department members Rudi Frühwirth (senior scientist) B,C, I Jakob Lettenbichler (diploma student) B Winni Mitaroff (senior scientist) B,I Moritz Nadler (doctoral student) B Manfred Valentan (former diploma student) I Wolfgang Waltenberger (junior scientist) C Edmund Widl (postdoc) C B …Belle/Belle II, C …CMS, I …ILD

4. Physics algorithms and data analysis 4Rudi Frühwirth11 November 20104Rudi Frühwirth4 Past activities ► DELPHI experiment (LEP) –Pattern recognition and geometrical alignment for the forward drift chambers built at HEPHY ► –Track fit in the forward region –Vertex fit ► CMS experiment (LHC) –Adaptive track fit and multi-track fit –Electron track fit with Gaussian-sum filter –Linear and adaptive vertex fit ►

5. Physics algorithms and data analysis 5Rudi Frühwirth11 November 20105Rudi Frühwirth5 Tracks Outlying track Adaptive fitter Linear fitter Linear and adaptive vertex fitter

6. Physics algorithms and data analysis 6Rudi Frühwirth11 November 20106Rudi Frühwirth6 Past activities ► Generic developments –Fast track fitting on the Riemann sphere –Mixture approximations of electron bremsstrahlung and multiple scattering ► –Robust mode estimation –Analytical formulas for track resolution ► Generic Software –LicToy: Fast simulation and reconstruction tool –JDOT: Detector optimization package –RAVE: Vertex reconstruction toolkit Solid line – true pdf, dashed line – semi-Gaussian mixture, dotted line – Gaussian mixture, dashed-dotted line – single Gaussian (Highland) Mixture models of multiple scattering

7. Physics algorithms and data analysis 7Rudi Frühwirth11 November 20107Rudi Frühwirth7 Current activities ► CMS tracker alignment –Kalman alignment algorithm –Validated on collision data –Two-track constraints being adapted to other CMS alignment algorithms ► ► CMS physics analysis –Semi-leptonic SUSY search and OSETs

8. Physics algorithms and data analysis 8Rudi Frühwirth11 November 20108Rudi Frühwirth8 Current activities Effect of alignment on momentum resolution, simulated data

9. Physics algorithms and data analysis 9Rudi Frühwirth11 November 20109Rudi Frühwirth9 Current activities ► Belle II tracking –Contribution to the Technical Design Report –Track finding in the Silicon Vertex Detector –Precision track fitting in the Silicon Vertex Detector for low momentum tracks –Methods for determination of the material distribution ► Belle II vertexing –Vertex toolkit (RAVE) to be introduced into the new framework

10. Physics algorithms and data analysis 10Rudi Frühwirth11 November 201010Rudi Frühwirth10 Current activities ► ILD tracking –Detector studies with LicToy tool completed, contribution to Letter of Intent –Responsibility for the forward track fit –EU funds available for a student ► ILD vertexing –Vertex toolkit (RAVE) ported to framework –Validated sucessfully

11. Physics algorithms and data analysis 11Rudi Frühwirth11 November 201011Rudi Frühwirth Recently finished theses E. Widl (Vienna UT, PhD) Global alignment of the CMS tracker (2008) Victor Hess-Prize 2009 of the Austrian Physical Society for the best thesis in nuclear and particle physics ► S. Federmann (Univ. Vienna, Diploma) Optimization of the Multi-Vertex Fitter for CMS Inner Tracker (2009) M. Valentan (Vienna UT, Diploma) Tracking detector optimization for collider experiments with fast simulation and by analytical methods (2009)

12. Physics algorithms and data analysis 12Rudi Frühwirth11 November 201012Rudi Frühwirth Theses in progress M. Nadler (Vienna UT, PhD) Precision track fit in the Belle II SVD (working title) J. Lettenbichler (Univ. Vienna, Diploma) Track finding in the Belle II SVD (working title) Lectures R. Frühwirth (Vienna UT): Statistik (Lecture, 2h, summer term) Statistische Methoden der Datenanalyse (Lecture, 2h, winter term)

13. Physics algorithms and data analysis 13Rudi Frühwirth11 November 201013Rudi Frühwirth CERN School of Computing 2003: Organization of the school in Krems (AT) Since 2004: Convener for Physics Computing Since 2004: Lecturer “Introduction into Physics Computing” Since 2007: Chairman of the Advisory Committee

14. Physics algorithms and data analysis 14Rudi Frühwirth11 November 201014Rudi Frühwirth External Collaborations ► Track and vertex reconstruction –A. Strandlie (Gjøvik University College, Norway) –Adaptive filters in track and vertex estimation –Long and fruitful collaboration –Recent summary in Rev. Mod. Phys. 82 (2010) 1419 ► ► Clustering of proteomics data –S. Pyne, D. Mani (Broad Institute of MIT & Harvard, USA) –Adapt vertex finder to 2D-clustering of peptides –Gives better cluster quality, faster than current method by at least an order of magnitude

15. Physics algorithms and data analysis 15Rudi Frühwirth11 November 201015Rudi Frühwirth External Collaborations ► Markov chain Monte Carlo for generalized linear models –S. Frühwirth-Schnatter (JKU Linz, Austria) –Mixture models for various distributions ► Variational Bayes methods –M. Wand (University of Wollongong, Australia) –Mixture models of intractable distributions ► Imaging of ultra-cold atoms –J. Schmiedmayer (Institute of Atomic and Subatomic Physics, Vienna UT) –Improve statistical analysis of CCD images of ultra-cold atoms

16. Physics algorithms and data analysis 16Rudi Frühwirth11 November 201016 Journal papers 2005-2010 Group-specific papers in refereed journals –Nucl. Instrum. Meth. A:10 –J. Instrumentation:2 –J. Phys. G:2 –IEEE Trans. Nucl. Sci.:2 –Comput. Stat. Data Anal.:2 –Comput. Phys. Commun:1 –Austrian J. of Statistics:1 –Rev. Mod. Phys.:1

17. Physics algorithms and data analysis 17Rudi Frühwirth11 November 201017 Book contributions R. Frühwirth, A. Strandlie: “Pattern recognition and reconstruction” In: Landolt-Börnstein New Series I/21B1, Springer, to appear in 2011 M. Krammer, W. Mitaroff: “Tracking Detectors” In: Handbook of Particle Detection and Imaging, Springer, to appear in 2011 S. Frühwirth-Schnatter, R. Frühwirth: “Data Augmentation and MCMC for Binary and Multinomial Logit Models” In: Statistical Modelling and Regression Structures, Physica Verlag, 2010

18. Physics algorithms and data analysis 18Rudi Frühwirth11 November 201018 Conference Contributions 2005 – 2010 Advanced Computing and Analysis Techniques: 2010, 2005 Computing in High Energy Physics: 2009, 2008, 2007, 2006 IEEE Nuclear Science Symposium: 2008, 2006 Vienna Conference on Instrumentation: 2007 Various smaller conferences and workshops Published in respective Proceedings and J. Phys. Conf. Ser.

19. Physics algorithms and data analysis 19Rudi Frühwirth11 November 201019Rudi Frühwirth Outlook ► CMS –Alignment: maintenance of Kalman Alignment Algorithm, further development of two-track constraint formalism –Vertex fit: maintenance, further tuning with collision data –Electron fit: maintenance –Physics analysis: continue participation in SUSY searches and OSETs, technical support for quarkonia analysis

20. Physics algorithms and data analysis 20Rudi Frühwirth11 November 201020Rudi Frühwirth20 Outlook ► Belle II –High-precision tracking: start implementation phase now, in collaboration with Munich and Karlsruhe –Track finding in the Silicon Vertex Detector: continue exploration phase ► ILD –Forward Tracking: ready for implementation phase

21. Physics algorithms and data analysis 21Rudi Frühwirth11 November 201021Rudi Frühwirth21 Thank you!

22. Physics algorithms and data analysis 22Rudi Frühwirth11 November 2010 Backup slides

23. Physics algorithms and data analysis 23Rudi Frühwirth11 November 201023Rudi Frühwirth Publications 2010 A. Strandlie, R. Frühwirth: Track and vertex reconstruction: From classical to adaptive methods. Review of Modern Physics 82, 1419-1458 S. Frühwirth-Schnatter, R. Frühwirth: Data Augmentation and MCMC for Binary and Multinomial Logit Models. In: Kneib, Thomas; Tutz, Gerhard (Eds.), Statistical Modelling and Regression Structures, Physica Verlag, Heidelberg, 2010.

24. Physics algorithms and data analysis 24Rudi Frühwirth11 November 201024Rudi Frühwirth Conferences, Workshops and Seminars ACAT 2010 (Jaipur): invited talk (RF) Workshop for Future Challenges in Tracking and Trigger Concepts (GSI): invited talk (RF) Workshop on Topologies for Early LHC Searches (SLAC): 2 CMS talks (WW) MPI Munich Kolloquium: invited seminar (RF) Belle II Tracking Workshop (Munich): 3 talks (MN,WW,RF)

25. Physics algorithms and data analysis 25Rudi Frühwirth11 November 201025Rudi Frühwirth CMS Global Alignment Hit residuals from three track-based algorithms: HIP (solid), Millepede (dashed), and Kalman alignment algorithm (dotted).

26. Physics algorithms and data analysis 26Rudi Frühwirth11 November 201026Rudi Frühwirth26 Material Estimation ► Optimization of material description –Started beginning 2010, part of PhD thesis (MN) –Estimate amount and possibly location of material along a track –Similar to alignment, but mathematically more challenging –First results with simulated tracks available –Best case scenario (perfect alignment, perfect knowledge of resolution, perfect track finding)

27. Physics algorithms and data analysis 27Rudi Frühwirth11 November 201027Rudi Frühwirth27 Material Estimation ► Methods –Global optimization of probability distributions Slow, poor scalability –Estimation of energy loss and multiple scattering distributions in regression model Limited sensitivity to material –Estimation of energy loss and multiple scattering distributions by forward/backward Kalman filter; material estimation by maximum likelihood fit Maximal sensitivity

28. Physics algorithms and data analysis 28Rudi Frühwirth11 November 201028Rudi Frühwirth28 Evolution of χ 2 probability distributions (energy loss only)

29. Physics algorithms and data analysis 29Rudi Frühwirth11 November 201029Rudi Frühwirth29 Evolution of χ 2 probability distributions (energy loss+multiple scattering)

30. Physics algorithms and data analysis 30Rudi Frühwirth11 November 201030Rudi Frühwirth30 Development of χ 2 probabilities (energy loss only)

31. Physics algorithms and data analysis 31Rudi Frühwirth11 November 201031Rudi Frühwirth31 Development of χ 2 probabilities (MS only)