1. Thomas RufVELO RZ ProjectionFebruary 2005

2. Motivation Find useful projections which help to debug the reconstruction algorithms. Event display useful to look for the unexpected.

3. Thomas RufVELO RZ ProjectionFebruary 2005 VELO RZ view RZ projection: R = sqrt(x 2 + y 2 ), x>0 R = -sqrt(x 2 + y 2 ), x<0 Scale: R:Z = 1:8.4 Tracks crossing VELO halves might look strange, however less busy plot compared to +RZ projection Projection only makes sense around VELO R-strips  points Phi-strips  vertical lines Selected MCParticles can be displayed in 3d with corresponding detector hits and reconstructed track(s)

4. Thomas RufVELO RZ ProjectionFebruary 2005 Extrapolations MCParticles: Production vertex inside Velo and decay vertex outside VELO: Straight line defined by momentum vector Production vertex outside Velo and decay vertex outside VELO: Straight line connecting production vertex and decay vertices Production vertex inside Velo and decay vertex inside VELO: Straight line connecting production vertex and decay vertex Tracks: Use of parabolic extrapolator if states with momentum information available, otherwise straight line between states Modifications to SoMCParticleCnv and SoTrStoredTrackCnv not directly related to RZ projection

5. Thomas RufVELO RZ ProjectionFebruary 2005 Associations New Associations entered: MCParticle_Clusters VeloCluster_MCParticles Would be nice to have a generic cluster object. Doesn’t exist at the moment, therefore association needs to be implemented for every cluster type. Modifications to SoEvent/Types.cpp, Panoramix/Callback.cpp and Onx/Pages.onx In picking mode, selecting object and clicking right mouse button:

6. Thomas RufVELO RZ ProjectionFebruary 2005 Display Vertices: Production vertex: Interaction vertex: MCParticles: e,u, ,k,p from B : red Other particles associated to tracks : golden

7. Thomas RufVELO RZ ProjectionFebruary 2005 Display VELO clusters: Used R-clusters : red Unused R-clusters : white Phi clusters: magenta Tracks: VELO back: green yellow VELO : green VELO-TT: cyan Forward: blue Match: skyblue Match ForwardVELO VELO back Velo-TT

8. Thomas RufVELO RZ ProjectionFebruary 2005 Examples Tracks crossing detector halves Why does x-slope changes ? Problem with extrapolator ? All events are from B  D*  No trigger applied

9. Thomas RufVELO RZ ProjectionFebruary 2005 Missing b-tracks I KL decay b-track, non-reconstructed  go to 3d view Velo noise ?

10. Thomas RufVELO RZ ProjectionFebruary 2005 3d View

11. Thomas RufVELO RZ ProjectionFebruary 2005 Missing b-tracks Ib

12. Thomas RufVELO RZ ProjectionFebruary 2005 100  m Missing b-tracks II

13. Thomas RufVELO RZ ProjectionFebruary 2005 100  m Missing b-tracks IIb decay Not enough hits ?

14. Thomas RufVELO RZ ProjectionFebruary 2005 Ghosts and Clones Downstream, 3d Match track and forward track Forward track is ghost, however 

15. Thomas RufVELO RZ ProjectionFebruary 2005 Upstream, 2d However, match track badly extrapolated to primary vertex Ghosts and Clones, cont.

16. Thomas RufVELO RZ ProjectionFebruary 2005 Precise tracking 100  m

17. Thomas RufVELO RZ ProjectionFebruary 2005 Converted Photons

18. Thomas RufVELO RZ ProjectionFebruary 2005 Converted Photons cont.

19. Thomas RufVELO RZ ProjectionFebruary 2005 Conversion reconstructed  conversion

20. Thomas RufVELO RZ ProjectionFebruary 2005 K short 100  m KsKs

21. Thomas RufVELO RZ ProjectionFebruary 2005 Pile Up 3 primary vertices 100  m

22. Thomas RufVELO RZ ProjectionFebruary 2005 Busy Event I 100  m Busy Event Backward Velo tracks cleaner than forward ?

23. Thomas RufVELO RZ ProjectionFebruary 2005 Busy Event II Backward Velo tracks cleaner than forward ?

24. Thomas RufVELO RZ ProjectionFebruary 2005 Clean Event I Clean Event However all B-decay tracks outside acceptance

25. Thomas RufVELO RZ ProjectionFebruary 2005 Clean Event II 100  m Another Clean Event with most B-decay tracks outside acceptance

26. Thomas RufVELO RZ ProjectionFebruary 2005 MC Truth Need scale ! Select D* decay tracks and display in 3d 

27. Thomas RufVELO RZ ProjectionFebruary 2005 To reconstruction

28. Thomas RufVELO RZ ProjectionFebruary 2005 Random Observations I Forward track with only 1 r-cluster ?

29. Thomas RufVELO RZ ProjectionFebruary 2005 Random Observations II Velo-TT tracks, extrapolation ?, 0 charge

30. Thomas RufVELO RZ ProjectionFebruary 2005 Random Observations III Not all Velo hits are used

31. Thomas RufVELO RZ ProjectionFebruary 2005 Random Observations IIIa Not all Velo hits are used Kaon decay

32. Thomas RufVELO RZ ProjectionFebruary 2005 Code Modifications SoEvent/Types.cpp Added bcflag property Associations SoEvent/SoMCParticleCnv.cpp Display of vertices Support for RZ projection, more straight line segments inside VELO SoEvent/SoTrStoredTrackCnv.cpp Support for RZ projection, more straight line segments inside VELO SbProjector.cxx: Added –ZR projection Temporarily moved to SoEvent/src Several Python scripts: truf_xxx.py

33. Thomas RufVELO RZ ProjectionFebruary 2005 Interactivity and Python If Panoramix is started from Python, you can exit Panoramix temporarily and access the event information directly using Python Example: Access to objects in any keyed container: After you finished, type to return to Panoramix Also possible to execute any Python script from Panoramix command line using sys_import(‘myscript’)

34. Thomas RufVELO RZ ProjectionFebruary 2005 End