Aspects of LAr Reconstruction S. Rajagopalan ATLAS Week June 4, 2001.
-
Upload
oswin-giles-butler -
Category
Documents
-
view
215 -
download
0
Transcript of Aspects of LAr Reconstruction S. Rajagopalan ATLAS Week June 4, 2001.
Aspects of LAr ReconstructionAspects of LAr Reconstruction
S. RajagopalanS. Rajagopalan
ATLAS WeekATLAS Week
June 4, 2001June 4, 2001
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
OverviewOverview
Calorimeter Reconstruction in ATRECON J. Schwindling et. al.J. Schwindling et. al. Successfully used in Physics TDRSuccessfully used in Physics TDR Now used as a benchmark for testing new codeNow used as a benchmark for testing new code
Migration to OO Work began in October 1999Work began in October 1999 Primary people involved today are: Primary people involved today are: (~ 5 FTE for (~ 5 FTE for
2001)2001)F. Lanni, H. Ma, S. Rajagopalan, K. Yip (BNL)F. Lanni, H. Ma, S. Rajagopalan, K. Yip (BNL)
A. Radu, M. Wielers (Triumf)A. Radu, M. Wielers (Triumf)
J. Collot, F. Ohlsson-Malek, S. Albrand (Grenoble)J. Collot, F. Ohlsson-Malek, S. Albrand (Grenoble)
P. Loch (Arizona)P. Loch (Arizona)
J. Schwindling, J.P. Meyer (Saclay)J. Schwindling, J.P. Meyer (Saclay)
E. Frank, A. Gupta, F. Merritt (Chicago) : TileE. Frank, A. Gupta, F. Merritt (Chicago) : Tile
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Major Milestones MetMajor Milestones Met Early design in PASO: Early design in PASO: Jan. 2000Jan. 2000 Migrate to Athena: Migrate to Athena: May 2000May 2000
LAr Reconstruction used as a test bed for early AthenaLAr Reconstruction used as a test bed for early Athena First application software to successfully migrate to AthenaFirst application software to successfully migrate to Athena
3 working days at LBL3 working days at LBL
First Common Calorimeter InterfacesFirst Common Calorimeter Interfaces Oct. 2000Oct. 2000 QA review of then available components QA review of then available components Dec. 2000Dec. 2000
S. Albrand (Grenoble) S. Albrand (Grenoble) Combined Reconstruction (egamma) Combined Reconstruction (egamma) Jan. 2001Jan. 2001 Process Process GEANT4GEANT4 LAr Hits (Root Objects) LAr Hits (Root Objects) Mar. 2001Mar. 2001 Lund ReleaseLund Release June 2001June 2001
Establishing most of the reconstruction chainEstablishing most of the reconstruction chain From G3/G4 Hits to Particle IdentificationFrom G3/G4 Hits to Particle Identification
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Algorithms & DataObjectsAlgorithms & DataObjects The design/packaging of the LAr reconstruction The design/packaging of the LAr reconstruction
programs follow the basic principle of the Athena programs follow the basic principle of the Athena FrameworkFramework
Data ObjectData Object
eg: A collection of cellseg: A collection of cells
Data ObjectData Object
eg: A collection of clusterseg: A collection of clusters
Algorithm(s)Algorithm(s)
ClusteringClusteringalgorithmsalgorithms+ associated+ associatedcorrectionscorrections
Data Objects reside in the Transient Data Store (TDS). Data Objects reside in the Transient Data Store (TDS).
Algorithms produce Data Objects and record them in the TDS.Algorithms produce Data Objects and record them in the TDS.
If reading/writing a DataObject from/to disk (persistent media), If reading/writing a DataObject from/to disk (persistent media),
a converter needs to be provided.a converter needs to be provided.
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Transient Event Store
Digits
Data FlowData Flow
D DD
c cc
C CC
CellReconstruction
Cells
ClusterReconstruction
Clusters
Analysis(ntuples)
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
LAr Data ClassesLAr Data Classes Data Objects proposed/implemented in March Data Objects proposed/implemented in March
20012001 J. Collot et. al.J. Collot et. al.
T.
D.
S.
Simulation Hits
DetRespSimulation RawChannels , Digits
CellBuilder
EventFilter/Builder
Electronics Calib
ClusterReconstruction
Hits
Cells
RawChannels , Digits
Digits
RawChannelsCells
Clusters
RawChannels , Digits
TBConvDigits
Test beam Zebra Tapes
HitConvHits
Objy , ROOT/IO
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
LAr Algorithm & Data ObjectsLAr Algorithm & Data Objects
Algorithms/(Packages) Data Objects
G3/G4 LArHit
Digitization LArDigit
ROD package LArRawChannel
Cell Reconstruction CaloCell
Tower Reconstruction CaloTower
Cluster Reconstruction CaloCluster
egammaRec egamma
tauRec tauObject
JetRec jet
MissingET MissingET
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Data Access by LAr AlgorithmsData Access by LAr Algorithms LArHit: Describes the G3/G4 LAr HitsLArHit: Describes the G3/G4 LAr Hits Collection of LArHit read from persistency Collection of LArHit read from persistency (Hong (Hong
Ma)Ma) using “Converters” in Athena using “Converters” in Athena Collection made available in the Transient Data Store Collection made available in the Transient Data Store
(TDS) for algorithms to process.(TDS) for algorithms to process.GEANT3GEANT3 Zebra Zebra FileFile
ZebraCnvZebraCnv RD RD EventEvent
LArHitLArHitZebraCnZebraCnvv LArHitLArHit
CollectionCollection
GEANT4GEANT4 Root FileRoot File LArHitLArHitRootCnvRootCnv
Work with Objectivity in progress, but not yet used by LAr
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
DigitizationDigitization Digitization Package: Digitization Package: (F. Lanni, J.P. Meyer, J. (F. Lanni, J.P. Meyer, J.
Schwindling)Schwindling) Emulation of the FEB in the Athena Framework:Emulation of the FEB in the Athena Framework:
Uses a simple gain selection mechanismUses a simple gain selection mechanism Input from G3 HitsInput from G3 Hits Additional Inputs: Gain, waveform profile, noise levelAdditional Inputs: Gain, waveform profile, noise level
Hardwired in code, needs to migrate to a Database.Hardwired in code, needs to migrate to a Database. Output: LArDigit containing 5 samples per channelOutput: LArDigit containing 5 samples per channel
Work in progress, first prototype is available.Work in progress, first prototype is available.
Adding Pile-up in Athena Adding Pile-up in Athena (M. Wielers)(M. Wielers) Cannot read multiple events in Athena at presentCannot read multiple events in Athena at present Can read old Zebra pile-up tapes (E Matrices) in AthenaCan read old Zebra pile-up tapes (E Matrices) in Athena
Signal+Pile-up events produced for “physics TDR” Signal+Pile-up events produced for “physics TDR” (Single electrons & photons, H (Single electrons & photons, H , jets), jets)
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Cluster Reconstruction on Pile-up Cluster Reconstruction on Pile-up EventsEvents
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Pile-up comparison with Pile-up comparison with ATRECONATRECON
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Kin YipKin Yip (+ B. Cleland, F. Lanni) (+ B. Cleland, F. Lanni)
Compute E, t, 2 from LArDigit (5 samples)
ROD Package in AthenaROD Package in Athena
Geant3Geant3
TestBeam DataTestBeam Data
2
A = observed amplitude in sample
and are optimal filtering coeffici
1E = A t = A
E
= A - (g E +
ents
g , g are the waveform paramete
t
rs
g E )
i i i ii i
i i i
i
i
i
i
i i
i
b
a
a
b
DigitizationDigitizationLArHitLArHit
ROD PackageROD PackageLArDigitLArDigit
LArRawChannelLArRawChannel
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Analysis of 50 GeV photons at Analysis of 50 GeV photons at =0.3 through =0.3 through Digitization & ROD packagesDigitization & ROD packages
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Cell ReconstructionCell Reconstruction
Several collections of CaloCell in Transient Data StoreSeveral collections of CaloCell in Transient Data Store Collections can be keyed by regionsCollections can be keyed by regions Collections can be keyed by algorithms producing Collections can be keyed by algorithms producing
themthem Downstream algorithms Downstream algorithms (Clustering/Particle ID)(Clustering/Particle ID) can simply can simply
request the CaloCell collections by specifying the keyrequest the CaloCell collections by specifying the key
Geant3Geant3 G3 Cell BuilderG3 Cell Builder CaloCellCaloCellLArHitLArHit
DigitizationDigitization
LArHit
RODROD CellBuilderCellBuilder CaloCellCaloCellLArDigitLArDigitLArRawChannelLArRawChannel
CaloCellCaloCellTileReconstructionTileReconstruction
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Tower ReconstructionTower Reconstruction
C C
C
CaloCell Collection
TowerBuilderTowerBuilder
T T
T
CaloTower Collection
T T
T
CaloTower Collection
TowerBuilderTowerBuilder
Configuration AR = 0.025 x 0.025
Configuration BR = 0.1 x 0.1
Key B Key A
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Cluster ReconstructionCluster Reconstruction Clustering AlgorithmsClustering Algorithms
Sliding Window (for EM and Hadronic Clusters)Sliding Window (for EM and Hadronic Clusters) Cone Algorithm (Fixed cone size around hottest cell)Cone Algorithm (Fixed cone size around hottest cell) Nearest Neighbour AlgorithmNearest Neighbour Algorithm
Clustering and needed Correction algorithms Clustering and needed Correction algorithms can be dynamically loadedcan be dynamically loaded
CaloClusterMakerCaloClusterMaker
Sliding WindowSliding WindowEnergyEnergy
CorrectionCorrectionPosition Position
CorrectionsCorrections
T TT
CaloTower Collection
CaloCluster
E, E, , , SamplingSampling…………list<CaloCell*>list<CaloCell*>
C CC
CaloCell Collection
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Comparison to Comparison to ATRECONATRECON
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Combined ReconstructionCombined Reconstruction
egamma Recegamma Rec (JBH, H. Ma, S. R., A. R., M. W.) First version provides Cluster-Track match,Shower Shape, Isolation… (missing conversions)Output in standard ntuples
CaloCluster, CaloCluster, SimpleTrackSimpleTrack
egammaegamma
Jet RecJet Rec (A. Gupta, F. Merritt, P. Loch, M. Wielers)KT Algorithm implementation. Most work by Tile, LAr beginning to join in the effort
CaloObjectCaloObject
JetJet
tau Rectau Rec (L. Vacavant, I.H., F.P., S.R.)First version in 2.0.0 (Lund) based on Phys. TDR cutsEM Radius, EM Strips, Isolation, # tracksOutput in standard ntuples
CaloCluster, CaloCluster, SimpleTrackSimpleTrack
tau Objecttau Object
Missing ETMissing ET (B. Caron)First version for Lund Releasebased on CaloCell Energies only
CaloCellCaloCell
MissingETMissingET
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
User Feedback/ValidationUser Feedback/Validation Quality Assurance : Quality Assurance : (S. Albrand)(S. Albrand)
Some of the recommendation already implementedSome of the recommendation already implemented
Extensive comparison between Atrecon & AthenaExtensive comparison between Atrecon & Athena FairouzFairouz studies of B studies of B J/ J/ ( ( ) )
http://isnwww.in2p3.fr/atlas/fairouz/physics/athena.html Statistically same, per event differences being Statistically same, per event differences being
understoodunderstood
Validation of software requested on pre-selected physics processes by NEWNEW users to Athena.
Z ee M. Losty (TRIUMF) H E. Tournefier (Grenoble) tau analysis F. Paige, D. Cavelli Jets, MissingET B. Caron, J. Pinfold
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Recent PlotsRecent Plots
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
-> -> analysis analysis (F. Ohlsson-Malek)
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Shower Shape ComparisonShower Shape Comparison Atrecon-Athena in EM Sampling 2 (A. Radu, M. (A. Radu, M.
Wielers)Wielers)
R = E(3x5)/E(7x7) w = width (3x5) E = 20 GeV e-
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
Other DetailsOther Details Particle ID strategiesParticle ID strategies IKinematic InterfaceIKinematic Interface
Proposal by ATLFAST group needs review/adoptionProposal by ATLFAST group needs review/adoption Event Filter requirementsEvent Filter requirements Adoption of new framework featuresAdoption of new framework features
StoreGate, Data Links, PersistencyStoreGate, Data Links, Persistency Using Detector Description in ReconstructionUsing Detector Description in Reconstruction
Hardwired in code at presentHardwired in code at present work in progress to read from DB (MySQL, Objectivity)work in progress to read from DB (MySQL, Objectivity)
Persistency support (Objectivity, Root)Persistency support (Objectivity, Root) Documentation: Documentation:
http://atlas.web.cern.ch/Atlas/GROUPS/LIQARGON/software/Reconstrhttp://atlas.web.cern.ch/Atlas/GROUPS/LIQARGON/software/Reconstruction/uction/
ATLAS Week, 4 June 2001ATLAS Week, 4 June 2001LAr ReconstructionLAr Reconstruction
ConclusionConclusion
A central framework that is evolving to provide robust A central framework that is evolving to provide robust supportsupport
The reconstruction design has been built over this The reconstruction design has been built over this frameworkframework
Much of the ‘Fortran’ code has been migrated.Much of the ‘Fortran’ code has been migrated. Validation ongoing, but results are promising.Validation ongoing, but results are promising.
It now paves the way for work in:It now paves the way for work in: optimizing and developing new algorithmsoptimizing and developing new algorithms Physics and Detector performance studiesPhysics and Detector performance studies