1. Physics Software Towards first Physics data Reconstruction Alignment
Tracking
Particle ID
Alignment
MonteCarlo Simulations
Physics Software Project Leader: Thomas Ruf(CERN)
Deputy Project Leader: Patrick Koppenburg (Imperial College)
Thomas Ruf Physics Software LHCC comprehensive review

2. LHCb Software Overview
Based on Gaudi framework
LCG packages: COOL, ROOT, …
Ext. Libraries: AIDA, BOOST, PYTHON, OpenScientist,…
Major LHCb libraries: LBCOM, LHCB, REC, PHYS, ONLINE, HLT, ALIGNMENT
Applications:
GAUSS Event Generation and Detector Simulation Output: MC hits
BOOLE Digitization Output: Raw Event
BRUNEL Reconstruction Output: DST
DaVinci Physics Analysis Output: DST, ETC
Panoramix Event Display, interactive analysis
Moore High Level trigger
Thomas Ruf Physics Software LHCC comprehensive review

3. Tracking Major achievements in 2007 Tracking framework Tf
Common basis for all pattern recognition algorithm
Used in High Level Trigger and Offline
Tracking Coordinator : Matthew Needham (CERN)
Present: Stephanie Hansmann-Menzemer (Heidelberg)
Thomas Ruf Physics Software LHCC comprehensive review

4. New framework
Thomas Ruf Physics Software LHCC comprehensive review

5. Tracking Major achievements in 2007 Tracking framework Tf Trackfit
Common basis for all pattern recognition algorithm
Used in High Level Trigger and Offline
Trackfit
Speed: various improvements in geometry and material lookup, kalman fit itself
DC06: ~30 ms/track, Now: ~10(5) ms/track additional 40% gain from 64bit machines
0.22 s/event with fast geometry
Momentum resolution
Thomas Ruf Physics Software LHCC comprehensive review

6. Trackfit
Thomas Ruf Physics Software LHCC comprehensive review

7. Tracking on First Data Assume Current MC somehow realistic
Pythia not completely off, primaries properly simulated
GEANT4 not completely off, secondaries properly simulated
Subdetectors and DAQ debugged and major errors fixed
(e.g. threshold cuts properly set)
(Tracking also provides tools for the subdetector debugging)
Thomas Ruf Physics Software LHCC comprehensive review

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13. Particle ID Major achievements in 2007
Improvements to Rich Reconstruction
Improved DLL Calibration, better Photon pre-selection
Particle ID Coordinator : Chris Jones (Cambridge)
Thomas Ruf Physics Software LHCC comprehensive review

14. First Data, PID Calibration
General Strategy: Use redundant information for cross calibration
Tracking, Mass and Vertex constraints
Thomas Ruf Physics Software LHCC comprehensive review

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16. First Data, PID Calibration
General Strategy: Use redundant information for cross calibration
Tracking, Mass and Vertex constraints
Calorimeter
MIP ECAL
MIP HCAL
Thomas Ruf Physics Software LHCC comprehensive review

17. Muon ID calibration
Thomas Ruf Physics Software LHCC comprehensive review

18. RICH PID Measure RICH detector properties from data
Cherenkov angle, refractive index and resolution
Photon Yield
Standard Candle: D* D0(Kp) p
isolated rings
Needs larger statistics, trigger important
Thomas Ruf Physics Software LHCC comprehensive review

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20. Alignment Survey Task Force started Autumn’07
Goal is to come up with the first LHCb Geometry based on Survey Data which can be used by the reconstruction
Velo, T and Muon alignment
Size of problem
Velo: 2x21x2 x = dof
IT : 7x4x4x3x = 2016 dof
OT : 9x4x4x3x = 2592 dof
Muon: ( )*2*5 *2 = ~ 3000 dof
Global Alignment Coordinator : Steve Blusk (Syracuse)
Thomas Ruf Physics Software LHCC comprehensive review

21. Velo Alignment Millepede based method Verified with testbeam
New: relative Phi position using residual distributions
Comparing software results with smartscope measurements for 6 sensors:
Conclusion:
Smartscope and software agree within 5micron
Alignment did not changed during transport
Thomas Ruf Physics Software LHCC comprehensive review

22. T and Muon Alignment Two methods Millepede based Kalman fit based
Linear or quadratic track model
Kalman fit based
uses LHCb track model
Both methods
are of “closed” form, correlations between residuals are taken into account via derivatives of track parameters with respect to alignment parameters
tested for IT and OT up to layer level
Module respectively Ladder level started
Study of weak modes ongoing using mbias events and different misalignment scenarios
 More details at agenda page of 2nd LHC Detector Alignment workshop
Thomas Ruf Physics Software LHCC comprehensive review

23. MonteCarlo Simulations
DC06 mass production used GEANT4 7.1.p01
Follow recent releases of GEANT4, v8 series, sometimes slight problems
Aim: Have a validated GEANT4 version by May to be used as basis for comparing and adjusting with real data
dE/dx in Silicon
µ ??
Thomas Ruf Physics Software LHCC comprehensive review

24. Miscellaneous GaudiPython
Enables reading event data in a simple way, as easy as reading an Ntuple with Paw.
No long studies of C++ and OO required
Extract from a GaudiPython Tutorial :
Thomas Ruf Physics Software LHCC comprehensive review

25. While waiting for beam
Thomas Ruf Physics Software LHCC comprehensive review

26. Backup Slides
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27. TF
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28. TF cont.
Thomas Ruf Physics Software LHCC comprehensive review

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