besiii offline software overview weidong li & yajun mao besiii collaboration meeting, beijing 12...
TRANSCRIPT
BESIII Offline Software Overview
Weidong Li & Yajun Mao
BESIII Collaboration Meeting, Beijing
12 January 2006
12/01/2006 W.Li and Y. Mao 2
Infrastructure and Environment Underlying framework
GAUDI (originally developed by LHCb)
Simulation
GEANT4
Other external LIBs:
CERNLIB, CLHEP, ROOT, AIDA, XercesC, GDML …
Database: PGSQL/MySQL
Software configuration management
CMT and CVS
Computer language: C++ (BESII legacy code written in Fortran )
Operation system: Redhat 7.3/gcc3.2
Reused code from Belle, BaBar, ATLAS,GLAST …
12/01/2006 W.Li and Y. Mao 3
Reconstruction
Calibration &Database
Framework CoreSoftware
Simulaton
Physics AnalysisSoftware
BES III Software
Organization Institutes participating
Institute of High Energy Physics
Peking University
Shandong University
University of Science and Technology of China
Hunan University
Zhejiang University
Joint Institute for Nuclear Research, Russian
Kanglin HeKanglin He
Huaimin LiuHuaimin LiuZepu MaoZepu Mao
Jinfa QiuJinfa QiuWeidong LiWeidong Li
12/01/2006 W.Li and Y. Mao 4
Event Data HEPEVT Data
Kinematics information only
RAW Data Delivered by DAQ for reconstruction
Byte stream format
Simulated Event Data Contain digits, hits and other MC truth
information
Ascii file format
REC & DST Data Reconstructed Data is event data written
as output of reconstruction procedure
DST Data is a reduced event representation suitable for analysis
Both in ROOT format
RAW DataRAW DataSimulatedSimulated
Event DataEvent Data
GeneratorGenerator
HEPEVTHEPEVT DataData
G4 SimulationG4 Simulation
ReconstructionReconstruction
Rec & DSTRec & DST DataData
12/01/2006 W.Li and Y. Mao 5
Event Data Conversion Services
AlgorithmA
AlgorithmB
AlgorithmC
Data T1
Data T2, T3
Data T2
Data T3, T4
Data T4
Data T5
T1
T5
Real data flow
Apparent data flow
T2
T4
T3
RootDstCnvSvc
RawDataCnvSvc
AsciiFileCnvSvc
REC&DSTData
RawData
Ascii Dump
PersistencyService
TransientData Store
12/01/2006 W.Li and Y. Mao 6
Detector Description Based GDML (Geometry Description Markup Language), a kind of XML developed
by GEANT4 group.
Peking University group expanded the GEANT4 Schema and developed a new ROOT Schema for BESIII applications.
GDML Detector Description has been used for simulation, event display and MUC reconstruction.
Classes for Simulation
Geometry, Materials,
Alignment…
XML description
Classesfor Reconstruction
Classesfor Event Display
ROOT SchemaROOT Schema
XM
L w
rite
r
GEANT4 Schema
12/01/2006 W.Li and Y. Mao 7
Access to Geometry Data
TOF
GeomSvc
EMC
GeomSvc
MUC
GeomSvc
MDC
GeomSvc
ApplicationApplication
LayerLayer
TOF
DAO
EMC
DAO
MUC
DAO
MDC
DAO
Database
Geometry, Materials
XML description
Objectsfor Reconstruction
Data AccessData Access
LayerLayer
12/01/2006 W.Li and Y. Mao 8
Event Display Tool: BesVis
Based on ROOT, OpenGL, X3D and XML
Support both 2D and 3D view
Operations and controls available through menu and toolbar items
First version was released in December 2005.
12/01/2006 W.Li and Y. Mao 9
Simulation Integration BES has ~30 event generators written in Fortran Use C++ Hepevt_Wrapper to access the kinematics information
generated by the generators
Transient Event Store
GeneratorGenerator
SimulatioSimulationn
SimulationSimulation
②②
①①
BOOST (BESIII Objected Oriented Simulation Tool) was originally developed in a independent framework.
Integration with BOOST simulation is based on ATLAS/Athena software.
Currently both BES generators and BOOST have been integrated with the offline framework.
12/01/2006 W.Li and Y. Mao 10
Calibration Status Framework is based on GLAST calibration infrastructure
Status Developed MDC, TOF and EMC calibration prototype algorithms
Defined calibration data for each sub-detector
Reconstruction algorithms are able to retrieved calibration constants through the framework.
calibUtil interface
Data (persistent)Metadata (persistent)
Dead chns(XML)
CAL calibs(ROOT)MySQL rdbms
Write/registerSearchRead
Signifies “uses” or “accesses”
12/01/2006 W.Li and Y. Mao 11
Drift Chamber Software Status Simulation
Stereo cells are described by G4TwistTube.
Digitization is based on parameters from test beam data.
The calibration algorithm contains correction to X-T relation, spatial resolution,T0, wire position,
time walk.
Reconstruction algorithms are: TrkReco and MdcPatRec. For single 1 GeV muons, both of them obtain: Efficiency: ~99%
Spatial resolution: ~110 μm
dE/dx resolution: ~6% consistent with detector design report.
12/01/2006 W.Li and Y. Mao 12
TOF Software Status Simulation
Two-layered structure for Barrel
Digitization takes into account: light production, light propagation and PMT response etc.
Intrinsic time resolution: 85 ps
Calibration & reconstruction Calibration algorithm includes
time correction, effective velocity and attenuation calibration.
Reconstruction results have been used in particle identification
12/01/2006 W.Li and Y. Mao 13
EM Calorimeter Software Status Simulation
End-cap is described by G4IrregBox.
Full simulation of readout electronics is included in digitization.
Energy calibration Digit calibration: converting ADC
channels into energy.
Cluster calibration: correcting non-linearity of readout signals.
Reconstruction ΔE/E = ~2% @1GeV
σz = 0.6 cm @1GeV
4E/E=[(p0/E) (p1/ E) p2]%
12/01/2006 W.Li and Y. Mao 14
Muon Counter Software Status Simulation
RPC as sensitive detector
Detailed to each read-out strip
Reconstruction Tracking algorithm is
seeded by the tracks extrapolated from MDC.
Searching for hits gap by gap within predefined windows.
Reconstruction efficiency: ~ 99% @ 1GeV
Ext track
Fired strips
Window
12/01/2006 W.Li and Y. Mao 15
Physics Analysis Software Status Prototype software for physics analysis
Analysis event data model
Analysis event builder
Kinematics fitting
Secondary vertex finding
Particle identification
Physicists already start checking physics performance.
12/01/2006 W.Li and Y. Mao 16
Online Event Selection Software
Fast reconstruction algorithms and steering prototypes that control event selection have been developed and tested in the online environment.
Accept
Reconstructionalgorithms
Consistentwith criteria
End of AlgSeq
N
N
Y
Reject
Y
Algorithmsequences
StepSequencer
Reconstructionresult
Share the same framework with offline.
Fast reconstruction algorithms shall be executed step by step according to the predefined sequences. In each step, event is rejected if it does not satisfy any selection criteria.
12/01/2006 W.Li and Y. Mao 17
Release Status BOSS alpha release
integration with BOOST simulation ( done )
Running the reconstruction chain for MDC, TOF, EMC and MUC can be achieved in the BOSS Gaudi framework. ( done )
EDM for both Raw Data and reconstructed data developed. Completion of fully functional Event Data I/O. ( done )
Status: published on 30th of May, 2005
BOSS beta release Simulation and reconstruction chain functions reasonably well and can
successfully process thousands of events. ( done )
Common physics analysis tools and utilities available. ( done )
Physics study in BOSS can start.
Status: published on 17th of November, 2005
12/01/2006 W.Li and Y. Mao 18
Progress since 2005 Annual Meeting Analysis software development
Analysis event builder (done)
Particle identification (done)
Secondary vertex finding (done)
Calibration infrastructure and algorithm prototypes (done)
Event Display Tool: BesVis (done)
Migration to GDML detector description (done for MUC )
Performance studies (ongoing)
Physics: efficiency and resolution
System: algorithms’ benchmarking and profiling, memory leakage etc.
Cavern backgrounds and realistic detector simulation (ongoing)
12/01/2006 W.Li and Y. Mao 19
Areas where work is needed Detector alignment, dead/hot channel services
Magnetic field service
Parameters database
Simulation of Level1 hardware trigger
Mixing of background events
Migration to Gaudi v16r4/LCGCMT_35 that has been tested in our target operation system (SLC3).
Analysis software will still evolve based on experience obtained from the current prototype.
Physics study for online Event Filter
Data Challenges
12/01/2006 W.Li and Y. Mao 20
Data Challenge (1) Motivation
To understand the BESIII computing environment CPU, storage and network requirements, system performances, bottle
necks, etc…
To check and validate the BESIII software
Iterate on a set of Data Challenges of increasing complexity Running ‘simulation’, ‘reconstruction’ and ‘analysis’ on a large scale
Testing calibration procedures
Adding trigger simulation and event filter algorithms
Producing physics results
12/01/2006 W.Li and Y. Mao 21
Data Challenge (2) It should include
Subsystem tests: simulation, calibration, reconstruction and analysis
Full offline chain test: GenerationGenerationsimulationsimulationdigitizationdigitization
backgroundbackground mixing mixing reconstructionreconstructionanalysisanalysis
Trigger/Event filter/Offline chain testTrigger/Event filter/Offline chain test
Stress tests for scaled systems (10%, 25%…)
12/01/2006 W.Li and Y. Mao 22
Summary A tremendous amount of progress in 2005
Simulation is in good shape and people are focusing on more and people are focusing on more realistic digitization procedures.realistic digitization procedures.
Calibration Infrastructure and prototype algorithms have been developed.
Reconstruction algorithms are being tuned for better performance.
Physics analysis prototype software are also developed and are being used in physics studies.
Data challenge and software performance optimization are two major tasks this year.
12/01/2006 W.Li and Y. Mao 23