Muon Alley Conditions

L0Muon confirmation

Muon PreTrigger

Logics

  • Create veloR (2d) tracks
  • Decode L0MuonCandidate
  • Match veloR track with L0MuonCandidate
  • Create Muon Segments from hits in M5-M2
  • Match veloR track with Muon segments if there was at least one matching with L0MuonCandidate
  • Reconstruct veloSpace (3d) tracks for those veloR flagged as muons
  • Match veloSpace track with L0MuonCandidate
  • Match veloSpace track with Muon segments if there was at least one matching with L0MuonCandidate
  • Reconstruct 2d PV vertex
  • Take muon pre trigger decision ++++ Cuts values in the Conditions Data Base
  • Parameters used to calibrate the energy of an L0muonCandidate (used in the matching of 2d and 3d tracks with L0muonCandidate)
  • Cut applied to the matching of 2d tracks with L0muonCandidate
    • Chisquare of matching = chi2DrDz + chi2Phi , where
      • chi2DrDz = ( deltaDrDz* deltaDrDz)/ (errdrdzL0*errdrdzL0 )
      • chi2Phi = ( deltaPhi*deltaPhi) / (errphiL0*errphiL0 + ephiTrack*ephiTrack)
      • originally determined from MC, chosen as to give the best purity, efficiency
  • Cut applied to the matching of 3d tracks with L0muonCandidate
    • Chisquare of matching = deltaX*deltaX + deltaY*deltaY , where
      • deltaX = q*(L0dxdz - trackDxDz)/errdxdzL0
      • deltaY = dydzSign*(L0dydz - trackDyDz)/errdydzL0
      • originally determined from MC, chosen as to give the best purity, efficiency
  • Cut applied in the Muon segments reconstruction
    • distance along X and along Y from the extrapolation of partial segment (Mi+1 - M5) in station Mi The cut varies with the region, so in total we have region*station*direction)=4*3*2=24 parameters.
  • Cuts applied to the matching of 2d tracks with Muon segments
    • Delta x [Region] : difference in x extrapolation of 2d track and muon segment to the zmagnet. One value for each muon region.
    • yTol : some tolerance to the extrapolation of muon segment to the r-phi velo sector
  • Cuts applied to the matching of 3d tracks with Muon segments
    • Delta x [Region] : difference in x extrapolation of 3d track and muon segment to the zmagnet. One value for each muon region.
    • Delta y [Region] : difference in y extrapolation of 3d track and muon segment to M2 z position. One value for each muon region.
  • Cuts applied to the HltPreMuonAlleyDecision
    • Single Muon
      • MuIPVeto - if IP for a single muon wrt any vertex < MuIPVeto, it points to a PV, discard it.
      • MuIPMinCut
      • PtSingleMuCut
    • Dimuon
      • diMuMassCut
      • diMuIPCut - smallest Ip of the two muons
    • JPsi
      • diMuMass > JPsiMass - MassWindowCut

Muon Trigger

  • Cuts applied to the matching of forward tracks with Muon segments
    • Delta pos : square difference among the extrapolation of long track and muon segment at M2 Z position. The difference is evaluated as sqrt(pow(Delta x,2)+pow(Delta y,2)/4). The applied cut is function of the momentum of the muon using the parametrized formula sqrt(a*a+b*b/(p*p)). In total we have 2 parameters: a and b.
  • Cuts applied to the HltMuonAlleyDecision
    • Single Muon
      • MuIPVeto - if IP for a single muon wrt any vertex < MuIPVeto, it points to a PV, discard it.
      • MuIPMinCut
      • PtSingleMuCut
    • Dimuon
      • diMuMassCut
      • diMuIPCut - smallest Ip of the two muons
    • JPsi
      • diMuMass > JPsiMass - MassWindowCut

Muon Alley Summary Box Content

  • MuonL0ConfirmationBox

  • MuonPreTriggerBox
    • Chisquare of matching of 2D to L0
    • Chisquare of matching of 3D to L0
    • delta x of matching of 2D to muon segments
    • delta x of matching of 3D to muon segments
    • delta y of matching of 3D to muon segments
    • smallest distance from L0 extrapolation to VELO sector board ( yTol monitoring)
    • Single muon Pt
    • Single muon Ip
    • Single Muon MuIPVeto
    • diMuMass
    • diMuIp
    • pointer to the 3D triggered tracks

  • MuonTriggerBox
    • delta x of matching of forwart track to muon segments
    • delta y of matching of forwart track to muon segments
    • Single muon Pt
    • Single muon Ip
    • Single Muon MuIPVeto
    • diMuMass
    • diMuIp
    • pointer to the forward triggered tracks

Muon Alley Monitoring

  • all summary box variables
  • Calibration L0 muon energy distribution
  • time evolution of mean values
  • Number of L0 Muon candidates
  • Number of 2D tracks
  • Number of 2D tracks flagged as Muons
  • Number of 2D tracks in a IP window
  • Number of 3D tracks in a IP window
  • Number of Velo-TT tracks (in a IP Window)
  • Number of 3D tracks
  • Number of 3D tracks flagged as Muons
  • Number of 3D tracks flagged as Muons found in TT
  • Number of forward tracks (in a IP Window)
  • Number of forward tracks
  • Number of 2D PV
  • Number of 3D PV
-- Sandra Amato - 26 May 2006

-- Alessia Satta -12 Jun 2006

-- Sandra Amato - 20 Jun 2006


This topic: LHCb > LHCbTrigger > MuonAlley
Topic revision: r12 - 2007-10-29 - StephenWotton
 
This site is powered by the TWiki collaboration platform Powered by PerlCopyright & 2008-2020 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback