// Default constructor
//
- fSensSelect = 0;
- fSensPlane = -1;
- fSensChamber = -1;
- fSensSector = -1;
- fSensSectorRange = 0;
+ fSensSelect = 0;
+ fSensPlane = -1;
+ fSensChamber = -1;
+ fSensSector = -1;
+ fSensSectorRange = 0;
- fDeltaE = NULL;
- fTR = NULL;
+ fDeltaE = NULL;
+ fDeltaG = NULL;
+ fTR = NULL;
+
+ fStepSize = 0.1;
+ fTypeOfStepManager = 2;
}
// Standard constructor for Transition Radiation Detector version 1
//
- fSensSelect = 0;
- fSensPlane = -1;
- fSensChamber = -1;
- fSensSector = -1;
- fSensSectorRange = 0;
+ fSensSelect = 0;
+ fSensPlane = -1;
+ fSensChamber = -1;
+ fSensSector = -1;
+ fSensSectorRange = 0;
- fDeltaE = NULL;
- fTR = NULL;
+ fDeltaE = NULL;
+ fDeltaG = NULL;
+ fTR = NULL;
+ fStepSize = 0.1;
+ fTypeOfStepManager = 2;
SetBufferSize(128000);
//
if (fDeltaE) delete fDeltaE;
+ if (fDeltaG) delete fDeltaG;
if (fTR) delete fTR;
}
// Copy function
//
- ((AliTRDv1 &) trd).fSensSelect = fSensSelect;
- ((AliTRDv1 &) trd).fSensPlane = fSensPlane;
- ((AliTRDv1 &) trd).fSensChamber = fSensChamber;
- ((AliTRDv1 &) trd).fSensSector = fSensSector;
- ((AliTRDv1 &) trd).fSensSectorRange = fSensSectorRange;
+ ((AliTRDv1 &) trd).fSensSelect = fSensSelect;
+ ((AliTRDv1 &) trd).fSensPlane = fSensPlane;
+ ((AliTRDv1 &) trd).fSensChamber = fSensChamber;
+ ((AliTRDv1 &) trd).fSensSector = fSensSector;
+ ((AliTRDv1 &) trd).fSensSectorRange = fSensSectorRange;
+
+ ((AliTRDv1 &) trd).fTypeOfStepManager = fTypeOfStepManager;
+ ((AliTRDv1 &) trd).fStepSize = fStepSize;
fDeltaE->Copy(*((AliTRDv1 &) trd).fDeltaE);
+ fDeltaG->Copy(*((AliTRDv1 &) trd).fDeltaG);
fTR->Copy(*((AliTRDv1 &) trd).fTR);
}
// is deposited.
if (sigma > 0.0) {
absLength = gRandom->Exp(1.0/sigma);
- if (absLength > AliTRDgeometry::DrThick()) continue;
+ if (absLength > (AliTRDgeometry::DrThick()
+ + AliTRDgeometry::AmThick())) {
+ continue;
+ }
}
else {
continue;
// Ermilova distribution for the delta-ray spectrum
Float_t poti = TMath::Log(kPoti);
Float_t eEnd = TMath::Log(kEend);
- fDeltaE = new TF1("deltae",Ermilova,poti,eEnd,0);
+
+ // Ermilova distribution for the delta-ray spectrum
+ fDeltaE = new TF1("deltae" ,Ermilova ,poti,eEnd,0);
+
+ // Geant3 distribution for the delta-ray spectrum
+ fDeltaG = new TF1("deltaeg",IntSpecGeant,poti,eEnd,0);
if(fDebug) {
printf("%s: ",ClassName());
//_____________________________________________________________________________
void AliTRDv1::StepManager()
+{
+ //
+ // Slow simulator. Every charged track produces electron cluster as hits
+ // along its path across the drift volume.
+ //
+
+ switch (fTypeOfStepManager) {
+ case 0 : StepManagerErmilova(); break; // 0 is Ermilova
+ case 1 : StepManagerGeant(); break; // 1 is Geant
+ case 2 : StepManagerFixedStep(); break; // 2 is fixed step
+ default : printf("<AliTRDv1::StepManager>: Not a valid Step Manager.\n");
+ }
+
+}
+
+//_____________________________________________________________________________
+void AliTRDv1::SelectStepManager(Int_t t)
+{
+ //
+ // Selects a step manager type:
+ // 0 - Ermilova
+ // 1 - Geant3
+ // 2 - Fixed step size
+ //
+
+ if (t == 1) {
+ printf("<AliTRDv1::SelectStepManager>: Sorry, Geant parametrization step"
+ "manager is not implemented yet. Please ask K.Oyama for detail.\n");
+ }
+
+ fTypeOfStepManager = t;
+ printf("<AliTRDv1::SelectStepManager>: Step Manager type %d was selected.\n"
+ , fTypeOfStepManager);
+
+}
+
+//_____________________________________________________________________________
+void AliTRDv1::StepManagerGeant()
+{
+ //
+ // Slow simulator. Every charged track produces electron cluster as hits
+ // along its path across the drift volume. The step size is set acording
+ // to Bethe-Bloch. The energy distribution of the delta electrons follows
+ // a spectrum taken from Geant3.
+ //
+
+ printf("AliTRDv1::StepManagerGeant: Not implemented yet.\n");
+
+}
+
+//_____________________________________________________________________________
+void AliTRDv1::StepManagerErmilova()
{
//
// Slow simulator. Every charged track produces electron cluster as hits
const Int_t kNcham = AliTRDgeometry::Ncham();
const Int_t kNdetsec = kNplan * kNcham;
- const Double_t kBig = 1.0E+12;
+ const Double_t kBig = 1.0E+12; // Infinitely big
+ const Float_t kWion = 22.04; // Ionization energy
+ const Float_t kPTotMaxEl = 0.002; // Maximum momentum for e+ e- g
- // Ionization energy
- const Float_t kWion = 22.04;
- // Maximum momentum for e+ e- g
- const Float_t kPTotMaxEl = 0.002;
// Minimum energy for the step size adjustment
const Float_t kEkinMinStep = 1.0e-5;
+
// Plateau value of the energy-loss for electron in xenon
// taken from: Allison + Comb, Ann. Rev. Nucl. Sci. (1980), 30, 253
//const Double_t kPlateau = 1.70;
// the averaged value (26/3/99)
const Float_t kPlateau = 1.55;
- // dN1/dx|min for the gas mixture (90% Xe + 10% CO2)
- const Float_t kPrim = 48.0;
+
+ const Float_t kPrim = 48.0; // dN1/dx|min for the gas mixture (90% Xe + 10% CO2)
// First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2)
const Float_t kPoti = 12.1;
- // PDG code electron
- const Int_t kPdgElectron = 11;
+ const Int_t kPdgElectron = 11; // PDG code electron
// Set the maximum step size to a very large number for all
// neutral particles and those outside the driftvolume
// The sector number (0 - 17)
// The numbering goes clockwise and starts at y = 0
- // Not fully consistent to new corrdinate schema!!!
Float_t phi = kRaddeg*TMath::ATan2(pos[0],pos[1]);
if (phi < 90.)
phi = phi + 270.;
// The detector number
det = fGeometry->GetDetector(pla,cha,sec);
- // Special hits and TR photons only in the drift region
+ // Special hits only in the drift region
if (drRegion) {
// Create a track reference at the entrance and
// Create a new dEdx hit
if (drRegion) {
- AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber(),det,hits,qTot,kTRUE);
+ AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber()
+ ,det,hits,qTot,kTRUE);
}
else {
- AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber(),det,hits,qTot,kFALSE);
+ AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber()
+ ,det,hits,qTot,kFALSE);
}
// Calculate the maximum step size for the next tracking step
}
+//_____________________________________________________________________________
+void AliTRDv1::StepManagerFixedStep()
+{
+ //
+ // 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.
+ //
+
+ Int_t pla = 0;
+ Int_t cha = 0;
+ Int_t sec = 0;
+ Int_t det = 0;
+ Int_t qTot;
+
+ Float_t hits[3];
+ Double_t eDep;
+
+ Bool_t drRegion = kFALSE;
+ Bool_t amRegion = kFALSE;
+
+ TString cIdCurrent;
+ TString cIdSensDr = "J";
+ TString cIdSensAm = "K";
+ Char_t cIdChamber[3];
+ cIdChamber[2] = 0;
+
+ TLorentzVector pos, mom;
+
+ const Int_t kNplan = AliTRDgeometry::Nplan();
+ const Int_t kNcham = AliTRDgeometry::Ncham();
+ const Int_t kNdetsec = kNplan * kNcham;
+
+ const Double_t kBig = 1.0E+12;
+
+ const Float_t kWion = 22.04; // Ionization energy
+ 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->IsTrackStop() ||
+ 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)
+ // The numbering goes clockwise and starts at y = 0
+ Float_t phi = kRaddeg*TMath::ATan2(pos[0],pos[1]);
+ if (phi < 90.) phi += 270.;
+ else phi -= 90.;
+ sec = ((Int_t) (phi / 20.));
+
+ // The plane and chamber number
+ cIdChamber[0] = cIdCurrent[2];
+ cIdChamber[1] = cIdCurrent[3];
+ Int_t idChamber = (atoi(cIdChamber) % kNdetsec);
+ cha = ((Int_t) idChamber / kNplan);
+ pla = ((Int_t) idChamber % kNplan);
+
+ // Check on selected volumes
+ Int_t addthishit = 1;
+ if(fSensSelect) {
+ if ((fSensPlane >= 0) && (pla != fSensPlane )) addthishit = 0;
+ if ((fSensChamber >= 0) && (cha != fSensChamber)) addthishit = 0;
+ if (fSensSector >= 0) {
+ Int_t sens1 = fSensSector;
+ Int_t sens2 = fSensSector + fSensSectorRange;
+ sens2 -= ((Int_t) (sens2 / AliTRDgeometry::Nsect())) * AliTRDgeometry::Nsect();
+ if (sens1 < sens2) {
+ if ((sec < sens1) || (sec >= sens2)) addthishit = 0;
+ }
+ else {
+ if ((sec < sens1) && (sec >= sens2)) addthishit = 0;
+ }
+ }
+ }
+
+ if (!addthishit) return;
+
+ det = fGeometry->GetDetector(pla,cha,sec); // The detector number
+
+ Int_t trkStat = 0; // 0: InFlight 1:Entering 2:Exiting
+
+ // Special hits only in the drift region
+ if (drRegion) {
+
+ // Create a track reference at the entrance and exit of each
+ // chamber that contain the momentum components of the particle
+
+ if (gMC->IsTrackEntering()) {
+ gMC->TrackMomentum(mom);
+ AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber());
+ trkStat = 1;
+ }
+ if (gMC->IsTrackExiting()) {
+ gMC->TrackMomentum(mom);
+ AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber());
+ trkStat = 2;
+ }
+
+ // Create the hits from TR photons
+ if (fTR) CreateTRhit(det);
+
+ }
+
+ // 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 / kWion);
+ AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber(),det,hits,qTot,drRegion);
+
+ // Set Maximum Step Size
+ // Produce only one hit if Ekin is below cutoff
+ if ((gMC->Etot() - gMC->TrackMass()) < kEkinMinStep) return;
+ gMC->SetMaxStep(fStepSize);
+
+}
+
//_____________________________________________________________________________
Double_t AliTRDv1::BetheBloch(Double_t bg)
{
}
+//_____________________________________________________________________________
+Double_t BetheBlochGeant(Double_t bg)
+{
+ //
+ // Return dN/dx (number of primary collisions per centimeter)
+ // for given beta*gamma factor.
+ //
+ // Implemented by K.Oyama according to GEANT 3 parametrization shown in
+ // A.Andronic's webpage: http://www-alice.gsi.de/trd/papers/dedx/dedx.html
+ // This must be used as a set with IntSpecGeant.
+ //
+
+ Double_t arr_g[20] = {
+ 1.100000, 1.200000, 1.300000, 1.500000,
+ 1.800000, 2.000000, 2.500000, 3.000000,
+ 4.000000, 7.000000, 10.000000, 20.000000,
+ 40.000000, 70.000000, 100.000000, 300.000000,
+ 600.000000, 1000.000000, 3000.000000, 10000.000000 };
+
+ Double_t arr_nc[20] = {
+ 75.009056, 45.508083, 35.299252, 27.116327,
+ 22.734999, 21.411915, 19.934095, 19.449375,
+ 19.344431, 20.185553, 21.027925, 22.912676,
+ 24.933352, 26.504053, 27.387468, 29.566597,
+ 30.353779, 30.787134, 31.129285, 31.157350 };
+
+ // betagamma to gamma
+ Double_t g = TMath::Sqrt( 1. + bg*bg );
+
+ // Find the index just before the point we need.
+ int i;
+ for( i = 0 ; i < 18 ; i++ )
+ if( arr_g[i] < g && arr_g[i+1] > g )
+ break;
+
+ // Simple interpolation.
+ Double_t pp = ((arr_nc[i+1] - arr_nc[i]) /
+ (arr_g[i+1]-arr_g[i])) * (g-arr_g[i]) + arr_nc[i];
+
+ return pp;
+
+}
+
//_____________________________________________________________________________
Double_t Ermilova(Double_t *x, Double_t *)
{
return dnde;
}
+
+//_____________________________________________________________________________
+Double_t IntSpecGeant(Double_t *x, Double_t *)
+{
+ //
+ // Integrated spectrum from Geant3
+ //
+
+ const Int_t n_pts = 83;
+ Double_t arr_e[n_pts] = {
+ 2.421257, 2.483278, 2.534301, 2.592230,
+ 2.672067, 2.813299, 3.015059, 3.216819,
+ 3.418579, 3.620338, 3.868209, 3.920198,
+ 3.978284, 4.063923, 4.186264, 4.308605,
+ 4.430946, 4.553288, 4.724261, 4.837736,
+ 4.999842, 5.161949, 5.324056, 5.486163,
+ 5.679688, 5.752998, 5.857728, 5.962457,
+ 6.067185, 6.171914, 6.315653, 6.393674,
+ 6.471694, 6.539689, 6.597658, 6.655627,
+ 6.710957, 6.763648, 6.816338, 6.876198,
+ 6.943227, 7.010257, 7.106285, 7.252151,
+ 7.460531, 7.668911, 7.877290, 8.085670,
+ 8.302979, 8.353585, 8.413120, 8.483500,
+ 8.541030, 8.592857, 8.668865, 8.820485,
+ 9.037086, 9.253686, 9.470286, 9.686887,
+ 9.930838, 9.994655, 10.085822, 10.176990,
+ 10.268158, 10.359325, 10.503614, 10.627565,
+ 10.804637, 10.981709, 11.158781, 11.335854,
+ 11.593397, 11.781165, 12.049404, 12.317644,
+ 12.585884, 12.854123, 14.278421, 16.975889,
+ 20.829416, 24.682943, 28.536469
+ };
+ Double_t arr_dndx[n_pts] = {
+ 19.344431, 18.664679, 18.136106, 17.567745,
+ 16.836426, 15.677382, 14.281277, 13.140237,
+ 12.207677, 11.445510, 10.697049, 10.562296,
+ 10.414673, 10.182341, 9.775256, 9.172330,
+ 8.240271, 6.898587, 4.808303, 3.889751,
+ 3.345288, 3.093431, 2.897347, 2.692470,
+ 2.436222, 2.340029, 2.208579, 2.086489,
+ 1.975535, 1.876519, 1.759626, 1.705024,
+ 1.656374, 1.502638, 1.330566, 1.200697,
+ 1.101168, 1.019323, 0.943867, 0.851951,
+ 0.755229, 0.671576, 0.570675, 0.449672,
+ 0.326722, 0.244225, 0.188225, 0.149608,
+ 0.121529, 0.116289, 0.110636, 0.103490,
+ 0.096147, 0.089191, 0.079780, 0.063927,
+ 0.047642, 0.036341, 0.028250, 0.022285,
+ 0.017291, 0.016211, 0.014802, 0.013533,
+ 0.012388, 0.011352, 0.009803, 0.008537,
+ 0.007039, 0.005829, 0.004843, 0.004034,
+ 0.003101, 0.002564, 0.001956, 0.001494,
+ 0.001142, 0.000873, 0.000210, 0.000014,
+ 0.000000, 0.000000, 0.000000
+ };
+
+ Int_t i;
+ Double_t energy = x[0];
+ Double_t dnde;
+
+ for( i = 0 ; i < n_pts ; i++ )
+ if( energy < arr_e[i] ) break;
+
+ if( i == 0 )
+ printf("Error in AliTRDv1::IntSpecGeant: "
+ "given energy value is too small or zero.\n");
+
+ // Interpolate
+ dnde = (arr_dndx[i-1] - arr_dndx[i]) / (arr_e[i] - arr_e[i-1]);
+
+ return dnde;
+
+}
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff