Difference between revisions of "Problems with track finding in CDC"
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[[File:lambda3.png]] | [[File:lambda3.png]] | ||
[[File:lambda4.png]] | [[File:lambda4.png]] | ||
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+ | (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: | ||
+ | |||
+ | [[File:lambda_new_algo.png]] |
Revision as of 10:33, 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: