Muon Software Status

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Muon Software Status

• Paul Balm
• March 16, 2001
• All D0 Meeting

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Outline

• Muon detector and reconstruction strategy
• Performance of local tracking
• muon system only
• Performance of the muonID package
• complete detector
• Performance of Central Track Matching at L3
• Conclusions and outlook

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Muon detector

• 80 geometric acceptance, for -2 lt h lt 2

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Reconstruction

• First find segments, then tracks
• Then do subdetector matching

C Layer
B Layer
Toroid
A Layer
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Implementation (offline)
D0Sim
MC chunks
RawDataChunk
muo_hitreco
XXXHitChunks
muo_segmentreco
(Muo)SegmentChunk
muo_trackreco
MuoTrackChunk
D0Reco
chpart_reco
ChargedParticleChunk
muo_caltrackreco
MuoCalTrackChunk
muonid
MuonParticleChunk
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Implementation at L3
Filter Scripts
Tools
Algorithms
USES
unpack_base unpack_muo_fe muon_geometry
L3TMuoUnpack
L3FMuoUnpack
muo_segment muo_trackreco muon_geometry
L3FMuoLocal
L3TMuoLocal
L3TMuoCentralMatch
L3FMuon
L3TMuon
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Local Tracking performance

• Single muons
• 5-100 GeV
• -2.5 lt h lt 2.5
• 1.1 min bias
• overall efficiency 46
• note includes geometrical acceptance!
• resolution 50 Sources
• misreconstructed tracks
• resolution of segments
• multiple scattering in the toroid

note resolution was lt20 at the end of 1999
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MuonID performance

• ( 10,000 ttbar events )
• Overall efficiency 671
• defined as all good muons/ MC muons
• GTrack in range -2 lt h lt 2
• includes GTrack efficiency, holes in muon
  system
• Mismatches (GTrack is not a muon)
• isolated muons about 10
• muons in jet many mismatches - but its physics
• punch-through, pions and kaons decaying in flight
• extra tight cut reduces this, but also cuts into
  efficiency
• possible improvements calorimeter matching,
  scintillator timing, global track fit

all passing all cuts good confirmed by MC
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L3 Central Track Matching performance

• Needs quite some more debugging
• Current matching efficiency about 20

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Conclusions Outlook

• Current status
• local tracking works - offline and at L3
• central track matching
• offline has better GTrack purity
• can be improved with calorimeter matching and
  global fit offline
• Outlook
• global fit requires thorough understanding of
  detector and errors - this will take time
• calorimeter matching coming soon