Kinematic fitting charged particles 11/16/11
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Looking at an all charged particle final state to study the state of the tracking code: \gamma p -> pi+ pi+ pi- pi- p.
- 50,000 events
- svn revision 8540
Kinematic fit
All combinations of track hypotheses that produce the correct final state are kinematically fit. Constraint is overall conservation of 4-momentum.
- 41% of events have sufficient particles (>=3 positive tracks, >=2 negative tracks)
- Of these, 9% have kinematic fit confidence level>1% (4% of total events)
3-momentum
Kinematic fit is dependent on errors, PID. Try to simplify things...
Look at events with exactly 5 tracks (3 positive, 2 negative) and look at sum of reconstructed 3-momentum from all tracks.
28% of events have exactly 5 tracks
2400 events in region outlined in red.