Enable backward search for iterations seeded by pixel quadruplets #387
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
mmasciov
added a commit
to trackreco/cmssw
that referenced
this pull request
Nov 24, 2021
makortel
pushed a commit
to trackreco/cmssw
that referenced
this pull request
Nov 25, 2021
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
PR description:
This PR is a further response following BTV investigations and aims at recovering as many pixel hits as possible compared to CKF, in the attempt to further improve impact parameter resolution. In summary:
(1) it enables backward search for iterations seeded by pixel quadruplets;
(2) it tightens the seed duplicate cleaning/merging.
For (1), first two BPIX layers in mkFit layer plan are inverted, only for iterations seeded by pixel quadruplets and only in transition regions and endcaps. In addition, hit selection windows are set also in pixel layers, to allow for backward search.
(2) allows for a further reduction in fakes+duplicates, with no cost in efficiency and with an increase of merged pixel hits in endcaps.
It supersedes PR #384.
PR validation (MTV results):
TTbar, PU=50 (vs. CKF and vs. PR386): https://mmasciovecchio.web.cern.ch/BTV_Nov2021/MTV_PR386_plusBkwSearchPixelQuad_TTbarPU50_122X/
10muPt0p2to10 (vs. CKF and vs. PR386): https://mmasciovecchio.web.cern.ch/BTV_Nov2021/MTV_PR386_plusBkwSearchPixelQuad_pixelLessSeedCleaning_10muPt0p2to10_122X/
High-pT QCD (cross-check vs. CKF and vs. mkFit as in 12_2_0_pre2): https://mmasciovecchio.web.cern.ch/BTV_Nov2021/MTV_highPtQCD_mkFit_for1220pre3/