Difference between revisions of "Problems with track finding in CDC"
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(→(March 5, 2012) Algorithm for dealing with bogus tracks) |
(→(March 5, 2012) Algorithm for dealing with bogus tracks) |
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[[File:lambda_candidates.gif]] | [[File:lambda_candidates.gif]] | ||
[[File:lambda_mass.gif]] | [[File:lambda_mass.gif]] | ||
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| + | Generate 2500 K0(short) events, 0.1-2.1 GeV/c | ||
| + | * Let GEANT decay the K0(short) | ||
| + | * Compare results with (red) and without (black) the new algorithm | ||
| + | |||
| + | [[File:kzero_candidates.gif]] | ||
| + | [[File:kzero_mass.gif]] | ||
Latest revision as of 11:21, 5 March 2012
Generated Lambda events with the particle gun. The following screen grabs from hdview2 illustrate a very common problem with these events: already used segments get associated erroneously with other already used segments to form bogus track candidates.
(March 5, 2012) Algorithm for dealing with bogus tracks
- Compare bit map of hits between two CDC seeds
- If 2 seeds share more than 90% of the same hits, keep the seed with the best χ^2/ndf from the circle fit
- If 2 seeds share more than 50% of the same hits (but less than 90%) and the reduced χ^2 values of the circle fits from each seed differ by more than 1, keep the seed with the best χ^2/ndf from the circle fit; otherwise keep both
The same event as above using the new algorithm:
Generated 2500 Λ events, 0.1-2.1 GeV/c
- Let GEANT decay the Λ
- Compare results with (red) and without (black) the new algorithm
Generate 2500 K0(short) events, 0.1-2.1 GeV/c
- Let GEANT decay the K0(short)
- Compare results with (red) and without (black) the new algorithm
