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Test Beam 2002. TestBeam Simulation and AliRoot. Paul Nilsson, SPD Group Meeting , August 26, 2003. Jan Conrad (CERN, Pixel Group) SPD general meeting May, 2004. Test Beam 2002 Analysis. Contents. Detour Status of SPD Test Beam DATA Analysis within AliRoot ( Bjorn Nilsen)
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Test Beam 2002 TestBeam Simulationand AliRoot Paul Nilsson, SPD Group Meeting , August 26, 2003 Jan Conrad (CERN, Pixel Group) SPD general meeting May, 2004 Test Beam 2002 Analysis P. Nilsson, SPD Group Meeting
Contents • Detour Status of SPD Test Beam DATA Analysis within AliRoot ( Bjorn Nilsen) • Test beam simulation within AliRoot • Current status • First look at simulated data • extensive To Do list NEW P. Nilsson, SPD Group Meeting
DETOUR: Data Analysis Status(on behalf of Bjorn Nilsen) • AliITSspdTestBeam.h, AliITSspdTestBeam.cxx and AliITSspdTestBeam2Digits.C • decode test beam data for 2002 • write digits (hits that fire a pixel) P. Nilsson, SPD Group Meeting
Detour: open problems • tested only one single file (small run) • tested only on 2002 data • does not write event information (reconstruction impossible, stops us from working with data f.t.t being) • includes violation of AliROOT coding conventions P. Nilsson, SPD Group Meeting
Motivation for AliRoot Simulation • Understanding of Pixel Response • Preparation for 2004 Test Beam • Migration of Analysis to AliRoot P. Nilsson, SPD Group Meeting
Test Beam Simulation within AliRoot: AliITSvSPD02.cxx Beta version: B. S. Nilsen • morph standard ALICE ITS simulation to test beam geometry (see AliITSvPPRcoarseasymm.cxx ) • some tricks necessary (segmentation/ material numbering etc …) AliITSvSPD03.cxx: more of the same ….. P. Nilsson, SPD Group Meeting
Short look at the class: void AliITSvSPD02::CreateGeometry(){ // define GEANT volumes and position them … gMC->Gsvolu("ITEL","BOX",idtmed[0],data,3); gMC->Gspos("ITEL",1,"ITSV",p00X,p00Y,p00Z,idrotm[0],"ONLY"); } void AliITSvSPD02::CreateMaterials(){ // what are the volumes made off ….. AliMaterial(1,"AIR$",……..); AliMedium(1,"AIR$",1,0,……); } void AliITSvSPD02::SetDefaultSimulation(){ // set response (thresholds, noise, etc …) } P. Nilsson, SPD Group Meeting
Geometry 2002 Trick: whole ladder Si (for segmentation, BN) No scintillators,no PCB P. Nilsson, SPD Group Meeting
Geometry 2003 No MWPC, no Plane 5 P. Nilsson, SPD Group Meeting
Simulation Configuration (2002) • Moving Particle gun • Nearly collinear protons ~ 350 GeV/c • Standard ALICE GEANT settings (galice.cuts) • Noise: 140 e, Thresh: 2310 e (PVTH 210) NEW P. Nilsson, SPD Group Meeting
First Results: Beam Spots 2002 P. Nilsson, SPD Group Meeting
BeamSpot simulation/data Delta Rays ??? (well …) P. Nilsson, SPD Group Meeting
Beam Spots 2002 cont’d P. Nilsson, SPD Group Meeting
Cluster Size 2002 Simulation Data Mean 3.7 Mean 1.62 Mean 1.60 P. Nilsson, SPD Group Meeting
Cluster Size 2002 cont’d P. Nilsson, SPD Group Meeting
Scans Simulation NEW ThresholdScan BIAS VOLTAGE? Data Angle Scan P. Nilsson, SPD Group Meeting
To Do: • basic checks and refinement • Scintillators, materials correct, settings correct, physics processes • implement further handles • residuals, etc. • Analysis within AliRoot (with Paul Nilsson, B.Nilsen) • work on response model • suggestions ? P. Nilsson, SPD Group Meeting
Conclusions • Work can start ! • 2002: • geometry implemented • ready for tuning (produces “data”) • first results not totally unphysical • 2003: • geometry implemented • needs some debugging ANY INPUT WELCOME !!!! P. Nilsson, SPD Group Meeting