X-Git-Url: http://git.uio.no/git/?p=u%2Fmrichter%2FAliRoot.git;a=blobdiff_plain;f=TRD%2FAliTRDv1.cxx;h=fcfa91679c88a2186c3ea9fddb7278c9fd71c85a;hp=aeed814aa500e04ede46731b57c70dad438fbd44;hb=c79857d5d6d529d151417960e1ba26e29a8c6eb6;hpb=82bbf98a94bcd028c83705fc1b282167db395328 diff --git a/TRD/AliTRDv1.cxx b/TRD/AliTRDv1.cxx index aeed814aa50..fcfa91679c8 100644 --- a/TRD/AliTRDv1.cxx +++ b/TRD/AliTRDv1.cxx @@ -1,75 +1,237 @@ -/////////////////////////////////////////////////////////////////////////////// -// // -// Transition Radiation Detector version 1 -- coarse simulation // -// This version has two detector arms, leaving the space in front of the // -// HMPID and PHOS empty // -// // -//Begin_Html -/* - -*/ -//End_Html -// // -// // -/////////////////////////////////////////////////////////////////////////////// - +/************************************************************************** + * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. * + * * + * Author: The ALICE Off-line Project. * + * Contributors are mentioned in the code where appropriate. * + * * + * Permission to use, copy, modify and distribute this software and its * + * documentation strictly for non-commercial purposes is hereby granted * + * without fee, provided that the above copyright notice appears in all * + * copies and that both the copyright notice and this permission notice * + * appear in the supporting documentation. The authors make no claims * + * about the suitability of this software for any purpose. It is * + * provided "as is" without express or implied warranty. * + **************************************************************************/ + +/* $Id$ */ + +//////////////////////////////////////////////////////////////////////////// +// // +// Transition Radiation Detector version 1 -- slow simulator // +// // +//////////////////////////////////////////////////////////////////////////// + +#include #include #include -#include +#include +#include +#include +#include -#include "AliTRDv1.h" -#include "AliRun.h" +#include "AliTrackReference.h" #include "AliMC.h" -#include "AliConst.h" - +#include "AliRun.h" +#include "AliGeomManager.h" + +#include "AliTRDgeometry.h" +#include "AliTRDCommonParam.h" +#include "AliTRDsimTR.h" +#include "AliTRDv1.h" + ClassImp(AliTRDv1) + +//_____________________________________________________________________________ +AliTRDv1::AliTRDv1() + :AliTRD() + ,fTRon(kFALSE) + ,fTR(NULL) + ,fStepSize(0) + ,fWion(0) +{ + // + // Default constructor + // + +} //_____________________________________________________________________________ AliTRDv1::AliTRDv1(const char *name, const char *title) - :AliTRD(name, title) + :AliTRD(name,title) + ,fTRon(kTRUE) + ,fTR(NULL) + ,fStepSize(0.1) + ,fWion(0) { // - // Standard constructor for the Transition Radiation Detector version 1 + // Standard constructor for Transition Radiation Detector version 1 // - fIdSens = 0; - fHitsOn = 0; + SetBufferSize(128000); + + if (AliTRDCommonParam::Instance()->IsXenon()) { + fWion = 23.53; // Ionization energy XeCO2 (85/15) + } + else if (AliTRDCommonParam::Instance()->IsArgon()) { + fWion = 27.21; // Ionization energy ArCO2 (82/18) + } + else { + AliFatal("Wrong gas mixture"); + exit(1); + } + +} - fIdSpace1 = 0; - fIdSpace2 = 0; - fIdSpace3 = 0; +//_____________________________________________________________________________ +AliTRDv1::~AliTRDv1() +{ + // + // AliTRDv1 destructor + // - fIdChamber1 = 0; - fIdChamber2 = 0; - fIdChamber3 = 0; + if (fTR) { + delete fTR; + fTR = 0; + } } //_____________________________________________________________________________ -void AliTRDv1::CreateGeometry() +void AliTRDv1::AddAlignableVolumes() const { // - // Create the GEANT geometry for the Transition Radiation Detector - Version 1 - // This version covers only part of the azimuth. + // Create entries for alignable volumes associating the symbolic volume + // name with the corresponding volume path. Needs to be syncronized with + // eventual changes in the geometry. + // + + TString volPath; + TString symName; + + TString vpStr = "ALIC_1/B077_1/BSEGMO"; + TString vpApp1 = "_1/BTRD"; + TString vpApp2 = "_1"; + TString vpApp3a = "/UTR1_1/UTS1_1/UTI1_1/UT"; + TString vpApp3b = "/UTR2_1/UTS2_1/UTI2_1/UT"; + TString vpApp3c = "/UTR3_1/UTS3_1/UTI3_1/UT"; + + TString snStr = "TRD/sm"; + TString snApp1 = "/st"; + TString snApp2 = "/pl"; + + // + // The super modules + // The symbolic names are: TRD/sm00 + // ... + // TRD/sm17 + // + for (Int_t isector = 0; isector < AliTRDgeometry::Nsector(); isector++) { + + volPath = vpStr; + volPath += isector; + volPath += vpApp1; + volPath += isector; + volPath += vpApp2; + + symName = snStr; + symName += Form("%02d",isector); + + gGeoManager->SetAlignableEntry(symName.Data(),volPath.Data()); + + } + // - // Author: Christoph Blume (C.Blume@gsi.de) 20/07/99 + // The readout chambers + // The symbolic names are: TRD/sm00/st0/pl0 + // ... + // TRD/sm17/st4/pl5 // + AliGeomManager::ELayerID idTRD1 = AliGeomManager::kTRD1; + Int_t layer, modUID; + + for (Int_t isector = 0; isector < AliTRDgeometry::Nsector(); isector++) { + + if (fGeometry->GetSMstatus(isector) == 0) continue; + + for (Int_t istack = 0; istack < AliTRDgeometry::Nstack(); istack++) { + for (Int_t ilayer = 0; ilayer < AliTRDgeometry::Nlayer(); ilayer++) { + + layer = idTRD1 + ilayer; + modUID = AliGeomManager::LayerToVolUIDSafe(layer,isector*5+istack); + + Int_t idet = AliTRDgeometry::GetDetectorSec(ilayer,istack); + + volPath = vpStr; + volPath += isector; + volPath += vpApp1; + volPath += isector; + volPath += vpApp2; + switch (isector) { + case 13: + case 14: + case 15: + if (istack == 2) { + continue; + } + volPath += vpApp3c; + break; + case 11: + case 12: + volPath += vpApp3b; + break; + default: + volPath += vpApp3a; + }; + volPath += Form("%02d",idet); + volPath += vpApp2; + + symName = snStr; + symName += Form("%02d",isector); + symName += snApp1; + symName += istack; + symName += snApp2; + symName += ilayer; + + TGeoPNEntry *alignableEntry = + gGeoManager->SetAlignableEntry(symName.Data(),volPath.Data(),modUID); + + // Add the tracking to local matrix following the TPC example + if (alignableEntry) { + TGeoHMatrix *globMatrix = alignableEntry->GetGlobalOrig(); + Double_t sectorAngle = 20.0 * (isector % 18) + 10.0; + TGeoHMatrix *t2lMatrix = new TGeoHMatrix(); + t2lMatrix->RotateZ(sectorAngle); + t2lMatrix->MultiplyLeft(&(globMatrix->Inverse())); + alignableEntry->SetMatrix(t2lMatrix); + } + else { + AliError(Form("Alignable entry %s is not valid!",symName.Data())); + } + + } + } + } - Float_t xpos, ypos, zpos; +} + +//_____________________________________________________________________________ +void AliTRDv1::CreateGeometry() +{ + // + // Create the GEANT geometry for the Transition Radiation Detector - Version 1 + // This version covers the full azimuth. + // // Check that FRAME is there otherwise we have no place where to put the TRD - AliModule* FRAME = gAlice->GetModule("FRAME"); - if (!FRAME) return; + AliModule* frame = gAlice->GetModule("FRAME"); + if (!frame) { + AliError("TRD needs FRAME to be present\n"); + return; + } // Define the chambers AliTRD::CreateGeometry(); - // Position the the TRD-sectors only in one TRD-volume in the spaceframe - xpos = 0.; - ypos = 0.; - zpos = 0.; - gMC->Gspos("TRD ",1,"BTR1",xpos,ypos,zpos,0,"ONLY"); - } //_____________________________________________________________________________ @@ -83,103 +245,272 @@ void AliTRDv1::CreateMaterials() } +//_____________________________________________________________________________ +void AliTRDv1::CreateTRhit(Int_t det) +{ + // + // Creates an electron cluster from a TR photon. + // The photon is assumed to be created a the end of the radiator. The + // distance after which it deposits its energy takes into account the + // absorbtion of the entrance window and of the gas mixture in drift + // volume. + // + + // Maximum number of TR photons per track + const Int_t kNTR = 50; + + TLorentzVector mom; + TLorentzVector pos; + + Float_t eTR[kNTR]; + Int_t nTR; + + // Create TR photons + gMC->TrackMomentum(mom); + Float_t pTot = mom.Rho(); + fTR->CreatePhotons(11,pTot,nTR,eTR); + if (nTR > kNTR) { + AliFatal(Form("Boundary error: nTR = %d, kNTR = %d",nTR,kNTR)); + } + + // Loop through the TR photons + for (Int_t iTR = 0; iTR < nTR; iTR++) { + + Float_t energyMeV = eTR[iTR] * 0.001; + Float_t energyeV = eTR[iTR] * 1000.0; + Float_t absLength = 0.0; + Float_t sigma = 0.0; + + // Take the absorbtion in the entrance window into account + Double_t muMy = fTR->GetMuMy(energyMeV); + sigma = muMy * fFoilDensity; + if (sigma > 0.0) { + absLength = gRandom->Exp(1.0/sigma); + if (absLength < AliTRDgeometry::MyThick()) { + continue; + } + } + else { + continue; + } + + // The absorbtion cross sections in the drift gas + // Gas-mixture (Xe/CO2) + Double_t muNo = 0.0; + if (AliTRDCommonParam::Instance()->IsXenon()) { + muNo = fTR->GetMuXe(energyMeV); + } + else if (AliTRDCommonParam::Instance()->IsArgon()) { + muNo = fTR->GetMuAr(energyMeV); + } + Double_t muCO = fTR->GetMuCO(energyMeV); + sigma = (fGasNobleFraction * muNo + (1.0 - fGasNobleFraction) * muCO) + * fGasDensity + * fTR->GetTemp(); + + // The distance after which the energy of the TR photon + // is deposited. + if (sigma > 0.0) { + absLength = gRandom->Exp(1.0/sigma); + if (absLength > (AliTRDgeometry::DrThick() + + AliTRDgeometry::AmThick())) { + continue; + } + } + else { + continue; + } + + // The position of the absorbtion + Float_t posHit[3]; + gMC->TrackPosition(pos); + posHit[0] = pos[0] + mom[0] / pTot * absLength; + posHit[1] = pos[1] + mom[1] / pTot * absLength; + posHit[2] = pos[2] + mom[2] / pTot * absLength; + + // Create the charge + Int_t q = ((Int_t) (energyeV / fWion)); + + // Add the hit to the array. TR photon hits are marked + // by negative charge + AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber() + ,det + ,posHit + ,-q + ,gMC->TrackTime()*1.0e06 + ,kTRUE); + + } + +} + //_____________________________________________________________________________ void AliTRDv1::Init() { // - // Initialise the Transition Radiation Detector after the geometry is built + // Initialise Transition Radiation Detector after geometry has been built. // AliTRD::Init(); - for (Int_t i = 0; i < 80; i++) printf("*"); - printf("\n"); - - // Identifier of the sensitive volume (amplification region) - fIdSens = gMC->VolId("UL06"); + AliDebug(1,"Slow simulator\n"); - // Identifier of the TRD-spaceframe volumina - fIdSpace1 = gMC->VolId("B028"); - fIdSpace2 = gMC->VolId("B029"); - fIdSpace3 = gMC->VolId("B030"); + // Switch on TR simulation as default + if (!fTRon) { + AliInfo("TR simulation off"); + } + else { + fTR = new AliTRDsimTR(); + } - // Identifier of the TRD-driftchambers - fIdChamber1 = gMC->VolId("UCIO"); - fIdChamber2 = gMC->VolId("UCIM"); - fIdChamber3 = gMC->VolId("UCII"); + AliDebug(1,"+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++"); } //_____________________________________________________________________________ -void AliTRDv1::StepManager() +void AliTRDv1::StepManager() { // - // Procedure called at every step in the TRD - // Fast simulator. If switched on, a hit is produced when a track - // crosses the border between amplification region and pad plane. - // - - Int_t vol[3]; - Int_t iIdSens, icSens; - Int_t iIdSpace, icSpace; - Int_t iIdChamber, icChamber; - - Int_t secMap1[10] = { 3, 7, 8, 9, 10, 11, 2, 1, 18, 17 }; - Int_t secMap2[ 5] = { 16, 15, 14, 13, 12 }; - Int_t secMap3[ 3] = { 5, 6, 4 }; - - Float_t hits[4]; - - TLorentzVector p; - TClonesArray &lhits = *fHits; - - // Writing out hits enabled? - if (!(fHitsOn)) return; - - // Use only charged tracks and count them only once per volume - if (gMC->TrackCharge() && - gMC->IsTrackExiting()) { - - // Check on sensitive volume - iIdSens = gMC->CurrentVolID(icSens); - if (iIdSens == fIdSens) { - - gMC->TrackPosition(p); - for (Int_t i = 0; i < 3; i++) hits[i] = p[i]; - // No charge created - hits[3] = 0; - - iIdSpace = gMC->CurrentVolOffID(4,icSpace ); - iIdChamber = gMC->CurrentVolOffID(1,icChamber); - - // The sector number - if (iIdSpace == fIdSpace1) - vol[0] = secMap1[icSpace-1]; - else if (iIdSpace == fIdSpace2) - vol[0] = secMap2[icSpace-1]; - else if (iIdSpace == fIdSpace3) - vol[0] = secMap3[icSpace-1]; - - // The chamber number - // 1: outer left - // 2: middle left - // 3: inner - // 4: middle right - // 5: outer right - if (iIdChamber == fIdChamber1) - vol[1] = (hits[2] < 0 ? 1 : 5); - else if (iIdChamber == fIdChamber2) - vol[1] = (hits[2] < 0 ? 2 : 4); - else if (iIdChamber == fIdChamber3) - vol[1] = 3; - - // The plane number - vol[2] = icChamber - TMath::Nint((Float_t) (icChamber / 7)) * 6; - - new(lhits[fNhits++]) AliTRDhit(fIshunt,gAlice->CurrentTrack(),vol,hits); + // Slow simulator. Every charged track produces electron cluster as hits + // along its path across the drift volume. The step size is fixed in + // this version of the step manager. + // + // Works for Xe/CO2 as well as Ar/CO2 + // + // PDG code electron + const Int_t kPdgElectron = 11; + + Int_t layer = 0; + Int_t stack = 0; + Int_t sector = 0; + Int_t det = 0; + Int_t qTot; + + Float_t hits[3]; + Double_t eDep; + + Bool_t drRegion = kFALSE; + Bool_t amRegion = kFALSE; + + TString cIdPath; + Char_t cIdSector[3]; + cIdSector[2] = 0; + + TString cIdCurrent; + TString cIdSensDr = "J"; + TString cIdSensAm = "K"; + Char_t cIdChamber[3]; + cIdChamber[2] = 0; + + TLorentzVector pos; + TLorentzVector mom; + + const Int_t kNlayer = AliTRDgeometry::Nlayer(); + const Int_t kNstack = AliTRDgeometry::Nstack(); + const Int_t kNdetsec = kNlayer * kNstack; + + const Double_t kBig = 1.0e+12; + const Float_t kEkinMinStep = 1.0e-5; // Minimum energy for the step size adjustment + + // Set the maximum step size to a very large number for all + // neutral particles and those outside the driftvolume + gMC->SetMaxStep(kBig); + + // If not charged track or already stopped or disappeared, just return. + if ((!gMC->TrackCharge()) || + gMC->IsTrackDisappeared()) { + return; + } + + // Inside a sensitive volume? + cIdCurrent = gMC->CurrentVolName(); + + if (cIdSensDr == cIdCurrent[1]) { + drRegion = kTRUE; + } + if (cIdSensAm == cIdCurrent[1]) { + amRegion = kTRUE; + } + + if ((!drRegion) && + (!amRegion)) { + return; + } + + // The hit coordinates and charge + gMC->TrackPosition(pos); + hits[0] = pos[0]; + hits[1] = pos[1]; + hits[2] = pos[2]; + + // The sector number (0 - 17), according to standard coordinate system + cIdPath = gGeoManager->GetPath(); + cIdSector[0] = cIdPath[21]; + cIdSector[1] = cIdPath[22]; + sector = atoi(cIdSector); + + // The plane and chamber number + cIdChamber[0] = cIdCurrent[2]; + cIdChamber[1] = cIdCurrent[3]; + Int_t idChamber = (atoi(cIdChamber) % kNdetsec); + stack = ((Int_t) idChamber / kNlayer); + layer = ((Int_t) idChamber % kNlayer); + + // The detector number + det = fGeometry->GetDetector(layer,stack,sector); + + // 0: InFlight 1:Entering 2:Exiting + Int_t trkStat = 0; + + // Special hits only in the drift region + if ((drRegion) && + (gMC->IsTrackEntering())) { + + // Create a track reference at the entrance of each + // chamber that contains the momentum components of the particle + gMC->TrackMomentum(mom); + AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber(), AliTrackReference::kTRD); + trkStat = 1; + + // Create the hits from TR photons if electron/positron is + // entering the drift volume + if ((fTR) && + (TMath::Abs(gMC->TrackPid()) == kPdgElectron)) { + CreateTRhit(det); } - } + } + else if ((amRegion) && + (gMC->IsTrackExiting())) { + + // Create a track reference at the exit of each + // chamber that contains the momentum components of the particle + gMC->TrackMomentum(mom); + AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber(), AliTrackReference::kTRD); + trkStat = 2; + + } + + // Calculate the charge according to GEANT Edep + // Create a new dEdx hit + eDep = TMath::Max(gMC->Edep(),0.0) * 1.0e+09; + qTot = (Int_t) (eDep / fWion); + if ((qTot) || + (trkStat)) { + AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber() + ,det + ,hits + ,qTot + ,gMC->TrackTime()*1.0e06 + ,drRegion); + } + + // Set Maximum Step Size + // Produce only one hit if Ekin is below cutoff + if ((gMC->Etot() - gMC->TrackMass()) < kEkinMinStep) { + return; + } + gMC->SetMaxStep(fStepSize); }