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CLID ILD Reconstruction Status. Mark Thomson University of Cambridge. This Talk. Status of CLIC_ILD reconstruction path one outstanding cross-check we are ready to tag a release (see Andre’s talk) This is the final chance to comment on Detector timing assumptions - PowerPoint PPT Presentation
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Mark Thomson University of Cambridge
CLID ILD Reconstruction Status
Mark Thomson 2
Status of CLIC_ILD reconstruction path one outstanding cross-check we are ready to tag a release (see Andre’s talk)
This is the final chance to comment on Detector timing assumptions PFO timing selection cuts DST format
LCD WG6, 16/3/2011
This Talk
Thanks to many people in particular, Andre for keeping on top of all the small fixes Erik, Jacopo, Jean-Jacques for finding bugs/features Stephane for producing files with overlay …
Mark Thomson 3LCD WG6, 16/3/2011
Tracking with Overlay At last meeting still some questions regarding tracking efficiency with overlay Ran a quick sanity check: fire 10 GeV muons in random directions use full background overlay define efficiency “is there a reconstructed track within 0.1 GeV
of 10 GeV which is associated with the MC “physics muon”
cosQ
Histo = MC muonPoint = reco 10 GeV track
Mark Thomson 4LCD WG6, 16/3/2011
Limited statistics (no time), but no indication of major problems Hint of something at 10 degrees: FTD geometry ? Only 2 tracks from ~1000 with q>7 degrees not reconstructed
Q [deg]
Mark Thomson 5
Calorimeters Assume all hits have a timestamp
• currently no smearing of hit times, assumed ~ 2 ns Assume two hit separation limited to 20 ns
• Hits within 20 ns are merged (use time for highest ph hit) For ECAL/HCAL endcap reconstruction integrate over 10 ns For HCAL barrel integrate over 100 ns Silicon
Integrate over time window of 10 ns No accounting for multiple hit capability
• occupancies fairly low TPC
Integrate over full bunch-train Require a matched Si hit in the above 10 ns window For looping tracks, also require arrival at ECAL within 50 ns
LCD WG6, 16/3/2011
Detector Assumptions
Defines input to event reconstruction
Mark Thomson 6
Overlay Reconstruction Can now routinely process events with overlay !!! few minutes per event overlay 60 BXs gamma gamma -> hadrons (limited by fortran PatRec)
believe to be a good approximation accounts for almost all calorimeter background + TPC PatRec is not an issue (see ALICE reconstruction)
Compare overlay/non-overlay processing for 1 TeV Z event
LCD WG6, 16/3/2011
1.4 TeV of background (reconstructed particles) !
Mark Thomson 7
Reconstruction performed at the full overlay level Then apply optional cluster-based timing cuts Since clusters contain many hits, mean cluster time known well assuming single hit resolution of ~ ns implies offline cluster
times typically known to much better than 1 ns LHC experience suggests this is realistic
LCD WG6, 16/3/2011
PFO Selection
e.g. HCAL endcap (where occupancy is high)
t/ns
pT/GeV
Background peaks Around 5ns, i.e. half ofthe 10ns window
Mark Thomson 8
Offline cluster time cuts applied in: CLICPFOSelector calculates a robust mean charge-weighted time for each cluster
(finds median time, rejects outlying 10 % of hits) applies cuts at PFO level different cuts for Photons, Neutral hadrons and charged hadrons if enough hits, time obtained from ECAL
LCD WG6, 16/3/2011
CLICPFOSelector
A priori, not clear how extreme the timing cuts should be Requirements may depend on physics analysis Part of our study is to determine what is required ! Hence run three versions of CLICPFOSelector
• Default, Loose cuts, Tight cuts
For physics analysis, have four possible sets of PFOs • PandorPFANewPFOS• SelectedPandoraPFANewPFOs• LooseSelectedPandoraPFANewPFOs• TightSelectedPandoraPFANewPFOs
Mark Thomson 9
For each PFO type define two levels of timing cuts (tight, loose)
LCD WG6, 16/3/2011
PFO-based Timing Cuts
Cut Photon Neutral h ChargedMax pT to apply loose cut 4.0 GeV 8.0 GeV 4.0 GeVLoose timing cut 2.0 ns 2.5 GeV 3.0 nspT to apply tight cut 0.75 GeV 0.75 GeV 0.75 GeVTight cut 1.0 ns 1.5 ns 1.5 nsFar forward cosq 0.975 0.975 n/aFar forward loose cut 2.0 ns 2.0 nsFar forward tight cut 1.0 ns 1.0 nsTrack-only min pT 0.5 GeVTrack-only max time at ECAL 10 ns
Default cuts:
Mark Thomson 10LCD WG6, 16/3/2011
Cut Photon Neutral h ChargedMax pT to apply loose cut 4.0 GeV 8.0 GeV 4.0 GeVLoose timing cut 2.0 ns 2.5 GeV 3.0 nspT to apply tight cut 0.75 GeV 0.75 GeV 0.75 GeVTight cut 2.0 ns 1.5 ns 1.5 nsFar forward cosq 0.975 0.975 n/aFar forward loose cut 2.0 ns 2.5 nsFar forward tight cut 1.0 ns 1.5 nsTrack-only min pT 0.25 GeVTrack-only max time at ECAL n/a
Loose cuts:
Mark Thomson 11LCD WG6, 16/3/2011
Cut Photon Neutral h ChargedMax pT to apply loose cut 4.0 GeV 8.0 GeV 4.0 GeVLoose timing cut 2.0 ns 2.5 GeV 2.0 nspT to apply tight cut 1.0 GeV 1.0 GeV 1.0 GeVTight cut 1.0 ns 1.5 ns 1.0 nsFar forward cosq 0.95 0.95 n/aFar forward loose cut 2.0 ns 2.0 nsFar forward tight cut 1.0 ns 1.0 nsTrack-only min pT 1.0 GeVTrack-only max time at ECAL 10 ns
Tight cuts:
Mark Thomson 12
PandoraNewPFAs
LCD WG6, 16/3/2011
1.4 TeV of background !
Mark Thomson 13
LooseSelectedPandoraNewPFAs
LCD WG6, 16/3/2011
0.3 TeV of background
Mark Thomson 14
SelectedPandoraNewPFAs
LCD WG6, 16/3/2011
0.2 TeV of background
Mark Thomson 15
TightSelectedPandoraNewPFAs
LCD WG6, 16/3/2011
0.1 TeV of background
Mark Thomson 16
Since last meeting, implemented AOD (DST) writing greatly simplified based on LCIO subsets now only write out MC particles for Physics event
(not the overlayed background)
Collections kept tracks clusters pfos (x4) pfo -> mc relation skimmed mc particles from physics event
LCD WG6, 16/3/2011
AOD Format
Flavour tagging left to the analysis groups
Mark Thomson 17
AOD for single muon + overlay
LCD WG6, 16/3/2011
COLLECTION NAME COLLECTION TYPE # ELEMENTS================================================================LooseSelectedPandoraPFANewPFOs ReconstructedParticle 222MCParticlesSkimmed MCParticle 1PandoraPFANewClusters Cluster 751PandoraPFANewPFOs ReconstructedParticle 942RecoMCTruthLink LCRelation 942SelectedLDCTracks Track 701SelectedPandoraPFANewPFOs ReconstructedParticle 117TightSelectedPandoraPFANewPFOs ReconstructedParticle 48
Note: MC relations in AOD have to be used with care only “physics event” MCParticles are retained in AOD
Mark Thomson 18
Using PFO - MC relations
LCD WG6, 16/3/2011
LCObjectVec objectVec = m_pfoToMcNavigator->getRelatedToObjects(pPfo); if (objectVec.size() > 0) { for(unsigned int imc = 0; imc < objectVec.size(); imc++){
MCParticle * pMC = dynamic_cast<MCParticle*>(objectVec[imc]);// since only saving skimmed set of MC particles,
// check pMC points to an existing object if(m_mcSet.count(pMC)!=0){ physicsPfos.push_back(pPfo); physicsMatchedMcParticle.push_back(pMC);}else{ backgroundPfos.push_back(pPfo);}
}
LCCollection * col = evt->getCollection(m_inputMcParticleCollection.c_str()); int nelem = col->getNumberOfElements(); for (int iMc=0; iMc<= col->getNumberOfElements(); ++iMc){ MCParticle * pMc = dynamic_cast<MCParticle*>(col->getElementAt(iMc)); m_mcSet.insert(pMc); }
Mark Thomson 19
After all code included in IlcSoft v11-pre02 will ask DESY make tag very soon
Default “steering” files in StandardConfig/clic_cdr clic_ild_cdr_steering.xml clic_ild_cdr_steering_overlay.xml clic_ild_cdr_pandora_settings.xml clic_ild_cdr.gear
Plan is to process events with and without overlay to help to assess impact of background
non-overlay version is almost identical to overlay version
LCD WG6, 16/3/2011
Status of ILD Reconstruction
Mark Thomson 20LCD WG6, 16/3/2011
final steering files<execute> <processor name="MyOverlayTiming"/> <processor name="MyCLICCDRMaterialDB"/> <processor name="MyTPCDigiProcessor"/> <processor name="MyLEPTrackingProcessor"/> <processor name="MyVTXDigiProcessor"/> <processor name="MyNewFTDDigiProcessor"/> <processor name="MyETDDigiProcessor"/> <processor name="MyILDCaloDigi"/> <processor name="MySimpleMuonDigi"/> <processor name="MySiliconTrackingCLIC"/> <processor name="MyFullLDCTracking"/> <processor name="MyCLICTrackSelector"/> <processor name="MyV0Finder"/> <processor name="MyKinkFinder"/> <processor name="MyMarlinPandora"/> <processor name="MyRecoMcTruthLinker"/> <processor name="MyLCIOOutputProcessor"/> <processor name="MyDstWriter"/></execute>
Overlay version only
NBackground = 0.0NBackground = 3.2
Including calo timing cuts
MC Skimming for DST
Write AOD
Write REC file
Mark Thomson 21LCD WG6, 16/3/2011
Remaining Issues
*Need to request a tagged release of ILCSoft
NOTHING SIGNIFICANT*
