+/**************************************************************************
+ * 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 2 -- detailed simulation //
-// //
-//Begin_Html
-/*
-<img src="picts/AliTRDv2Class.gif">
-*/
-//End_Html
-// //
+// Transition Radiation Detector version 2 -- slow simulator with //
+// detailed geometry //
// //
///////////////////////////////////////////////////////////////////////////////
+#include <stdlib.h>
+
#include <TMath.h>
-#include <TVector.h>
-#include <TRandom.h>
+#include <TVirtualMC.h>
-#include "AliTRDv2.h"
-#include "AliTRDmatrix.h"
-#include "AliRun.h"
-#include "AliMC.h"
#include "AliConst.h"
+#include "AliRun.h"
+#include "AliTRDgeometryDetail.h"
+#include "AliTRDv2.h"
ClassImp(AliTRDv2)
-
-//_____________________________________________________________________________
-AliTRDv2::AliTRDv2(const char *name, const char *title)
- :AliTRD(name, title)
-{
- //
- // Standard constructor for Transition Radiation Detector version 2
- //
-
- fIdSens = 0;
-
- fIdSpace1 = 0;
- fIdSpace2 = 0;
- fIdSpace3 = 0;
-
- fIdChamber1 = 0;
- fIdChamber2 = 0;
- fIdChamber3 = 0;
-
- fSensSelect = 0;
- fSensPlane = 0;
- fSensChamber = 0;
- fSensSector = 0;
-
- for (Int_t iplan = 0; iplan < kNplan; iplan++) {
- for (Int_t icham = 0; icham < kNcham; icham++) {
- fRowMax[iplan][icham] = 0;
- }
- fColMax[iplan] = 0;
- }
- fTimeMax = 0;
-
- fRowPadSize = 0;
- fColPadSize = 0;
- fTimeBinSize = 0;
-
- fGasGain = 0;
- fNoise = 0;
- fChipGain = 0;
- fADCoutRange = 0;
- fADCinRange = 0;
- fADCthreshold = 0;
-
- fDiffusionT = 0;
- fDiffusionL = 0;
-
- fDeltaE = NULL;
-
- SetBufferSize(128000);
-
-}
-
-//_____________________________________________________________________________
-AliTRDv2::~AliTRDv2()
-{
-
- if (fDeltaE) delete fDeltaE;
-
-}
//_____________________________________________________________________________
-void AliTRDv2::CreateGeometry()
+AliTRDv2::AliTRDv2():AliTRDv1()
{
//
- // Create the GEANT geometry for the Transition Radiation Detector - Version 2
- // This version covers the full azimuth.
+ // Default constructor
//
- // Author: Christoph Blume (C.Blume@gsi.de) 20/07/99
- //
-
- Float_t xpos, ypos, zpos;
-
- // Check that FRAME is there otherwise we have no place where to put the TRD
- AliModule* FRAME = gAlice->GetModule("FRAME");
- if (!FRAME) return;
-
- // Define the chambers
- AliTRD::CreateGeometry();
-
- // Position the the TRD-sectors in all TRD-volumes in the spaceframe
- xpos = 0.;
- ypos = 0.;
- zpos = 0.;
- gMC->Gspos("TRD ",1,"BTR1",xpos,ypos,zpos,0,"ONLY");
- gMC->Gspos("TRD ",2,"BTR2",xpos,ypos,zpos,0,"ONLY");
- gMC->Gspos("TRD ",3,"BTR3",xpos,ypos,zpos,0,"ONLY");
}
//_____________________________________________________________________________
-void AliTRDv2::CreateMaterials()
-{
- //
- // Create materials for the Transition Radiation Detector version 2
- //
-
- AliTRD::CreateMaterials();
-
-}
-
-//_____________________________________________________________________________
-void AliTRDv2::Diffusion(Float_t driftlength, Float_t *xyz)
-{
- //
- // Applies the diffusion smearing to the position of a single electron
- //
-
- if ((driftlength > 0) &&
- (driftlength < kDrThick)) {
- Float_t driftSqrt = TMath::Sqrt(driftlength);
- Float_t sigmaT = driftSqrt * fDiffusionT;
- Float_t sigmaL = driftSqrt * fDiffusionL;
- xyz[0] = gRandom->Gaus(xyz[0], sigmaL);
- xyz[1] = gRandom->Gaus(xyz[1], sigmaT);
- xyz[2] = gRandom->Gaus(xyz[2], sigmaT);
- }
- else {
- xyz[0] = 0.0;
- xyz[1] = 0.0;
- xyz[2] = 0.0;
- }
-
-}
-
-//_____________________________________________________________________________
-void AliTRDv2::Hits2Digits()
+AliTRDv2::AliTRDv2(const char *name, const char *title)
+ :AliTRDv1(name, title)
{
//
- // Creates TRD digits from hits. This procedure includes the following:
- // - Diffusion
- // - Gas gain including fluctuations
- // - Pad-response (simple Gaussian approximation)
- // - Electronics noise
- // - Electronics gain
- // - Digitization
- // - ADC threshold
- // The corresponding parameter can be adjusted via the various Set-functions.
- // If these parameters are not explicitly set, default values are used (see
- // Init-function).
- // To produce digits from a galice.root file with TRD-hits use the
- // digitsCreate.C macro.
+ // Standard constructor for Transition Radiation Detector version 2
//
- printf(" Start creating digits\n");
-
- ///////////////////////////////////////////////////////////////
- // Parameter
- ///////////////////////////////////////////////////////////////
-
- // Converts number of electrons to fC
- const Float_t el2fC = 1.602E-19 * 1.0E15;
-
- ///////////////////////////////////////////////////////////////
-
- Int_t nBytes = 0;
-
- AliTRDhit *TRDhit;
-
- // Position of pad 0,0,0
- //
- // chambers seen from the top:
- // +----------------------------+
- // | |
- // | | ^
- // | | rphi|
- // | | |
- // |0 | |
- // +----------------------------+ +------>
- // z
- // chambers seen from the side: ^
- // +----------------------------+ time|
- // | | |
- // |0 | |
- // +----------------------------+ +------>
- // z
- //
- // The pad row (z-direction)
- Float_t row0[kNplan][kNcham];
- for (Int_t iplan = 0; iplan < kNplan; iplan++) {
- row0[iplan][0] = -fClengthI[iplan]/2. - fClengthM[iplan] - fClengthO[iplan]
- + kCcthick;
- row0[iplan][1] = -fClengthI[iplan]/2. - fClengthM[iplan]
- + kCcthick;
- row0[iplan][2] = -fClengthI[iplan]/2.
- + kCcthick;
- row0[iplan][3] = fClengthI[iplan]/2.
- + kCcthick;
- row0[iplan][4] = fClengthI[iplan]/2. + fClengthM[iplan]
- + kCcthick;
- }
- // The pad column (rphi-direction)
- Float_t col0[kNplan];
- for (Int_t iplan = 0; iplan < kNplan; iplan++) {
- col0[iplan] = -fCwidth[iplan]/2. + kCcthick;
- }
- // The time bucket
- Float_t time0[kNplan];
- for (Int_t iplan = 0; iplan < kNplan; iplan++) {
- time0[iplan] = kRmin + kCcframe/2. + kDrZpos - 0.5 * kDrThick
- + iplan * (kCheight + kCspace);
+ // Check that FRAME is there otherwise we have no place where to
+ // put TRD
+ AliModule* frame = gAlice->GetModule("FRAME");
+ if (!frame) {
+ Error("Ctor","TRD needs FRAME to be present\n");
+ exit(1);
}
- // Get the pointer to the hit tree
- TTree *HitTree = gAlice->TreeH();
- // Get the pointer to the digits tree
- TTree *DigitsTree = gAlice->TreeD();
-
- // Get the number of entries in the hit tree
- // (Number of primary particles creating a hit somewhere)
- Int_t nTrack = (Int_t) HitTree->GetEntries();
-
- Int_t chamBeg = 0;
- Int_t chamEnd = kNcham;
- if (fSensChamber) chamEnd = chamBeg = fSensChamber;
- Int_t planBeg = 0;
- Int_t planEnd = kNplan;
- if (fSensPlane) planEnd = planBeg = fSensPlane;
- Int_t sectBeg = 0;
- Int_t sectEnd = kNsect;
- if (fSensSector) sectEnd = sectBeg = fSensSector;
-
- // Loop through all the chambers
- for (Int_t icham = chamBeg; icham < chamEnd; icham++) {
- for (Int_t iplan = planBeg; iplan < planEnd; iplan++) {
- for (Int_t isect = sectBeg; isect < sectEnd; isect++) {
-
- printf(" Digitizing chamber %d, plane %d, sector %d\n"
- ,icham+1,iplan+1,isect+1);
-
- // Create a detector matrix to keep the signal and track numbers
- AliTRDmatrix *matrix = new AliTRDmatrix(fRowMax[iplan][icham]
- ,fColMax[iplan]
- ,fTimeMax
- ,isect+1,icham+1,iplan+1);
-
- // Loop through all entries in the tree
- for (Int_t iTrack = 0; iTrack < nTrack; iTrack++) {
-
- gAlice->ResetHits();
- nBytes += HitTree->GetEvent(iTrack);
-
- // Get the number of hits in the TRD created by this particle
- Int_t nHit = fHits->GetEntriesFast();
-
- // Loop through the TRD hits
- for (Int_t iHit = 0; iHit < nHit; iHit++) {
-
- if (!(TRDhit = (AliTRDhit *) fHits->UncheckedAt(iHit)))
- continue;
-
- Float_t x = TRDhit->fX;
- Float_t y = TRDhit->fY;
- Float_t z = TRDhit->fZ;
- Float_t q = TRDhit->fQ;
- Int_t track = TRDhit->fTrack;
- Int_t plane = TRDhit->fPlane;
- Int_t sector = TRDhit->fSector;
- Int_t chamber = TRDhit->fChamber;
-
- if ((sector != isect+1) ||
- (plane != iplan+1) ||
- (chamber != icham+1))
- continue;
-
- // Rotate the sectors on top of each other
- Float_t phi = 2.0 * kPI / (Float_t) kNsect
- * ((Float_t) sector - 0.5);
- Float_t xRot = -x * TMath::Cos(phi) + y * TMath::Sin(phi);
- Float_t yRot = x * TMath::Sin(phi) + y * TMath::Cos(phi);
- Float_t zRot = z;
-
- // The hit position in pad coordinates (center pad)
- // The pad row (z-direction)
- Int_t rowH = (Int_t) ((zRot - row0[iplan][icham]) / fRowPadSize);
- // The pad column (rphi-direction)
- Int_t colH = (Int_t) ((yRot - col0[iplan] ) / fColPadSize);
- // The time bucket
- Int_t timeH = (Int_t) ((xRot - time0[iplan] ) / fTimeBinSize);
-
- // Array to sum up the signal in a box surrounding the
- // hit postition
- const Int_t timeBox = 5;
- const Int_t colBox = 7;
- const Int_t rowBox = 5;
- Float_t signalSum[rowBox][colBox][timeBox];
- for (Int_t iRow = 0; iRow < rowBox; iRow++ ) {
- for (Int_t iCol = 0; iCol < colBox; iCol++ ) {
- for (Int_t iTime = 0; iTime < timeBox; iTime++) {
- signalSum[iRow][iCol][iTime] = 0;
- }
- }
- }
-
- // Loop over all electrons of this hit
- Int_t nEl = (Int_t) q;
- for (Int_t iEl = 0; iEl < nEl; iEl++) {
-
- // Apply the diffusion smearing
- Float_t driftlength = xRot - time0[iplan];
- Float_t xyz[3];
- xyz[0] = xRot;
- xyz[1] = yRot;
- xyz[2] = zRot;
- Diffusion(driftlength,xyz);
-
- // At this point absorption effects that depend on the
- // driftlength could be taken into account.
-
- // The electron position and the distance to the hit position
- // in pad units
- // The pad row (z-direction)
- Int_t rowE = (Int_t) ((xyz[2] - row0[iplan][icham]) / fRowPadSize);
- Int_t rowD = rowH - rowE;
- // The pad column (rphi-direction)
- Int_t colE = (Int_t) ((xyz[1] - col0[iplan] ) / fColPadSize);
- Int_t colD = colH - colE;
- // The time bucket
- Int_t timeE = (Int_t) ((xyz[0] - time0[iplan] ) / fTimeBinSize);
- Int_t timeD = timeH - timeE;
-
- // Apply the gas gain including fluctuations
- Int_t signal = (Int_t) (-fGasGain * TMath::Log(gRandom->Rndm()));
-
- // The distance of the electron to the center of the pad
- // in units of pad width
- Float_t dist = (xyz[1] - col0[iplan] - (colE + 0.5) * fColPadSize)
- / fColPadSize;
-
- // Sum up the signal in the different pixels
- // and apply the pad response
- Int_t rowIdx = rowD + (Int_t) ( rowBox / 2);
- Int_t colIdx = colD + (Int_t) ( colBox / 2);
- Int_t timeIdx = timeD + (Int_t) (timeBox / 2);
- signalSum[rowIdx][colIdx-1][timeIdx] += PadResponse(dist-1.) * signal;
- signalSum[rowIdx][colIdx ][timeIdx] += PadResponse(dist ) * signal;
- signalSum[rowIdx][colIdx+1][timeIdx] += PadResponse(dist+1.) * signal;
-
- }
-
- // Add the padcluster to the detector matrix
- for (Int_t iRow = 0; iRow < rowBox; iRow++ ) {
- for (Int_t iCol = 0; iCol < colBox; iCol++ ) {
- for (Int_t iTime = 0; iTime < timeBox; iTime++) {
-
- Int_t rowB = rowH + iRow - (Int_t) ( rowBox / 2);
- Int_t colB = colH + iCol - (Int_t) ( colBox / 2);
- Int_t timeB = timeH + iTime - (Int_t) (timeBox / 2);
-
- Float_t signalB = signalSum[iRow][iCol][iTime];
- if (signalB > 0.0) {
- matrix->AddSignal(rowB,colB,timeB,signalB);
- if (!(matrix->AddTrack(rowB,colB,timeB,track)))
- printf("More than three tracks in a pixel!\n");
- }
-
- }
- }
- }
-
- }
-
- }
-
- // Create the hits for this chamber
- for (Int_t iRow = 0; iRow < fRowMax[iplan][icham]; iRow++ ) {
- for (Int_t iCol = 0; iCol < fColMax[iplan] ; iCol++ ) {
- for (Int_t iTime = 0; iTime < fTimeMax ; iTime++) {
-
- Float_t signalAmp = matrix->GetSignal(iRow,iCol,iTime);
-
- // Add the noise
- signalAmp = TMath::Max(gRandom->Gaus(signalAmp,fNoise),0.0);
- // Convert to fC
- signalAmp *= el2fC;
- // Convert to mV
- signalAmp *= fChipGain;
- // Convert to ADC counts
- Int_t adc = (Int_t) (signalAmp * (fADCoutRange / fADCinRange));
-
- // Apply threshold on ADC value
- if (adc > fADCthreshold) {
-
- Int_t trackSave[3];
- for (Int_t ii = 0; ii < 3; ii++) {
- trackSave[ii] = matrix->GetTrack(iRow,iCol,iTime,ii);
- }
-
- Int_t digits[7];
- digits[0] = matrix->GetSector();
- digits[1] = matrix->GetChamber();
- digits[2] = matrix->GetPlane();
- digits[3] = iRow;
- digits[4] = iCol;
- digits[5] = iTime;
- digits[6] = adc;
-
- // Add this digit to the TClonesArray
- AddDigit(trackSave,digits);
-
- }
-
- }
- }
- }
-
- // Clean up
- delete matrix;
-
- }
- }
+ if (frame->IsVersion() == 1) {
+ // Detailed geometry without hole
+ if (fGeometry) delete fGeometry;
+ fGeometry = new AliTRDgeometryDetail();
}
-
- // Fill the digits-tree
- DigitsTree->Fill();
-
-}
-
-//_____________________________________________________________________________
-void AliTRDv2::Init()
-{
- //
- // Initialise Transition Radiation Detector after geometry has been built.
- // Includes the default settings of all parameter for the digitization.
- //
-
- AliTRD::Init();
-
- if (fSensPlane)
- printf(" Only plane %d is sensitive\n",fSensPlane);
- if (fSensChamber)
- printf(" Only chamber %d is sensitive\n",fSensChamber);
- if (fSensSector)
- printf(" Only sector %d is sensitive\n",fSensSector);
-
- for (Int_t i = 0; i < 80; i++) printf("*");
- printf("\n");
-
- // First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2)
- const Float_t kPoti = 12.1;
- // Maximum energy (50 keV);
- const Float_t kEend = 50000.0;
- // 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);
-
- // Identifier of the sensitive volume (drift region)
- fIdSens = gMC->VolId("UL05");
-
- // Identifier of the TRD-spaceframe volumina
- fIdSpace1 = gMC->VolId("B028");
- fIdSpace2 = gMC->VolId("B029");
- fIdSpace3 = gMC->VolId("B030");
-
- // Identifier of the TRD-driftchambers
- fIdChamber1 = gMC->VolId("UCIO");
- fIdChamber2 = gMC->VolId("UCIM");
- fIdChamber3 = gMC->VolId("UCII");
-
- // The default pad dimensions
- if (!(fRowPadSize)) fRowPadSize = 4.5;
- if (!(fColPadSize)) fColPadSize = 1.0;
- if (!(fTimeBinSize)) fTimeBinSize = 0.1;
-
- // The maximum number of pads
- for (Int_t iplan = 0; iplan < kNplan; iplan++) {
- // Rows
- fRowMax[iplan][0] = 1 + TMath::Nint((fClengthO[iplan] - 2. * kCcthick)
- / fRowPadSize - 0.5);
- fRowMax[iplan][1] = 1 + TMath::Nint((fClengthM[iplan] - 2. * kCcthick)
- / fRowPadSize - 0.5);
- fRowMax[iplan][2] = 1 + TMath::Nint((fClengthI[iplan] - 2. * kCcthick)
- / fRowPadSize - 0.5);
- fRowMax[iplan][3] = 1 + TMath::Nint((fClengthM[iplan] - 2. * kCcthick)
- / fRowPadSize - 0.5);
- fRowMax[iplan][4] = 1 + TMath::Nint((fClengthO[iplan] - 2. * kCcthick)
- / fRowPadSize - 0.5);
- // Columns
- fColMax[iplan] = 1 + TMath::Nint((fCwidth[iplan] - 2. * kCcthick)
- / fColPadSize - 0.5);
- }
- // Time buckets
- fTimeMax = 1 + TMath::Nint(kDrThick / fTimeBinSize - 0.5);
-
- // The default parameter for the digitization
- if (!(fGasGain)) fGasGain = 2.0E3;
- if (!(fNoise)) fNoise = 3000.;
- if (!(fChipGain)) fChipGain = 10.;
- if (!(fADCoutRange)) fADCoutRange = 255.;
- if (!(fADCinRange)) fADCinRange = 2000.;
- if (!(fADCthreshold)) fADCthreshold = 0;
-
- // Transverse and longitudinal diffusion coefficients (Xe/Isobutane)
- if (!(fDiffusionT)) fDiffusionT = 0.060;
- if (!(fDiffusionL)) fDiffusionL = 0.017;
-
-}
-
-//_____________________________________________________________________________
-void AliTRDv2::MakeBranch(Option_t* option)
-{
- //
- // Create Tree branches for the TRD digits.
- //
-
- Int_t buffersize = 4000;
- Char_t branchname[10];
-
- sprintf(branchname,"%s",GetName());
-
- AliDetector::MakeBranch(option);
-
- Char_t *D = strstr(option,"D");
- if (fDigits && gAlice->TreeD() && D) {
- gAlice->TreeD()->Branch(branchname,&fDigits, buffersize);
- printf("Making Branch %s for digits\n",branchname);
+ else {
+ Error("Ctor","Could not find valid FRAME version 1\n");
+ exit(1);
}
}
//_____________________________________________________________________________
-Float_t AliTRDv2::PadResponse(Float_t x)
+AliTRDv2::AliTRDv2(const AliTRDv2 &trd):AliTRDv1(trd)
{
//
- // The pad response for the chevron pads.
- // We use a simple Gaussian approximation which should be good
- // enough for our purpose.
+ // Copy constructor
//
- // The parameters for the response function
- const Float_t aa = 0.8872;
- const Float_t bb = -0.00573;
- const Float_t cc = 0.454;
- const Float_t cc2 = cc*cc;
-
- Float_t pr = aa * (bb + TMath::Exp(-x*x / (2. * cc2)));
-
- //TF1 *funPR = new TF1("funPR","[0]*([1]+exp(-x*x /(2.*[2])))",-3,3);
- //funPR->SetParameter(0,aa );
- //funPR->SetParameter(1,bb );
- //funPR->SetParameter(2,cc2);
- //
- //Float_t pr = funPR->Eval(distance);
- //
- //delete funPR;
-
- return (pr);
+ ((AliTRDv2 &) trd).Copy(*this);
}
//_____________________________________________________________________________
-void AliTRDv2::SetSensPlane(Int_t iplane)
+AliTRDv2::~AliTRDv2()
{
//
- // Defines the hit-sensitive plane (1-6)
+ // AliTRDv2 destructor
//
- if ((iplane < 0) || (iplane > 6)) {
- printf("Wrong input value: %d\n",iplane);
- printf("Use standard setting\n");
- fSensPlane = 0;
- fSensSelect = 0;
- return;
- }
-
- fSensSelect = 1;
- fSensPlane = iplane;
-
}
-
+
//_____________________________________________________________________________
-void AliTRDv2::SetSensChamber(Int_t ichamber)
+AliTRDv2 &AliTRDv2::operator=(const AliTRDv2 &trd)
{
//
- // Defines the hit-sensitive chamber (1-5)
+ // Assignment operator
//
- if ((ichamber < 0) || (ichamber > 5)) {
- printf("Wrong input value: %d\n",ichamber);
- printf("Use standard setting\n");
- fSensChamber = 0;
- fSensSelect = 0;
- return;
- }
-
- fSensSelect = 1;
- fSensChamber = ichamber;
+ if (this != &trd) ((AliTRDv2 &) trd).Copy(*this);
+ return *this;
}
-
+
//_____________________________________________________________________________
-void AliTRDv2::SetSensSector(Int_t isector)
+void AliTRDv2::Copy(TObject &trd)
{
//
- // Defines the hit-sensitive sector (1-18)
+ // Copy function
//
- if ((isector < 0) || (isector > 18)) {
- printf("Wrong input value: %d\n",isector);
- printf("Use standard setting\n");
- fSensSector = 0;
- fSensSelect = 0;
- return;
- }
-
- fSensSelect = 1;
- fSensSector = isector;
+ AliTRDv1::Copy(trd);
}
//_____________________________________________________________________________
-void AliTRDv2::StepManager()
+void AliTRDv2::CreateGeometry()
{
//
- // Called at every step in the Transition Radiation Detector version 2.
- // 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 Ermilova et al.
+ // Create the geometry for the Transition Radiation Detector version 2
//
- Int_t iIdSens, icSens;
- Int_t iIdSpace, icSpace;
- Int_t iIdChamber, icChamber;
- Int_t vol[3];
- Int_t iPid;
-
- 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];
- Float_t random[1];
- Float_t charge;
- Float_t aMass;
-
- Double_t pTot;
- Double_t qTot;
- Double_t eDelta;
- Double_t betaGamma, pp;
-
- TLorentzVector pos, mom;
- TClonesArray &lhits = *fHits;
-
- const Double_t kBig = 1.0E+12;
-
- // Ionization energy
- const Float_t kWion = 22.04;
- // Maximum energy for e+ e- g for the step-size calculation
- const Float_t kPTotMax = 0.002;
- // 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;
- // First ionization potential (eV) for the gas mixture (90% Xe + 10% CO2)
- const Float_t kPoti = 12.1;
-
- // Set the maximum step size to a very large number for all
- // neutral particles and those outside the driftvolume
- gMC->SetMaxStep(kBig);
-
- // Use only charged tracks
- if (( gMC->TrackCharge() ) &&
- (!gMC->IsTrackStop() ) &&
- (!gMC->IsTrackDisappeared())) {
-
- // Inside a sensitive volume?
- iIdSens = gMC->CurrentVolID(icSens);
- if (iIdSens == fIdSens) {
-
- iIdSpace = gMC->CurrentVolOffID(4,icSpace );
- iIdChamber = gMC->CurrentVolOffID(1,icChamber);
-
- // Calculate the energy of the delta-electrons
- eDelta = TMath::Exp(fDeltaE->GetRandom()) - kPoti;
- eDelta = TMath::Max(eDelta,0.0);
-
- // The number of secondary electrons created
- qTot = (Double_t) ((Int_t) (eDelta / kWion) + 1);
-
- // The hit coordinates and charge
- gMC->TrackPosition(pos);
- hits[0] = pos[0];
- hits[1] = pos[1];
- hits[2] = pos[2];
- hits[3] = qTot;
-
- // 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;
-
- // Check on selected volumes
- Int_t addthishit = 1;
- if (fSensSelect) {
- if ((fSensPlane) && (vol[2] != fSensPlane )) addthishit = 0;
- if ((fSensChamber) && (vol[1] != fSensChamber)) addthishit = 0;
- if ((fSensSector) && (vol[0] != fSensSector )) addthishit = 0;
- }
-
- // Add this hit
- if (addthishit) {
-
- new(lhits[fNhits++]) AliTRDhit(fIshunt,gAlice->CurrentTrack(),vol,hits);
-
- // The energy loss according to Bethe Bloch
- gMC->TrackMomentum(mom);
- pTot = mom.Rho();
- iPid = gMC->TrackPid();
- if ( (iPid > 3) ||
- ((iPid <= 3) && (pTot < kPTotMax))) {
- aMass = gMC->TrackMass();
- betaGamma = pTot / aMass;
- pp = kPrim * BetheBloch(betaGamma);
- // Take charge > 1 into account
- charge = gMC->TrackCharge();
- if (TMath::Abs(charge) > 1) pp = pp * charge*charge;
- }
- // Electrons above 20 Mev/c are at the plateau
- else {
- pp = kPrim * kPlateau;
- }
-
- // Calculate the maximum step size for the next tracking step
- if (pp > 0) {
- do
- gMC->Rndm(random,1);
- while ((random[0] == 1.) || (random[0] == 0.));
- gMC->SetMaxStep( - TMath::Log(random[0]) / pp);
- }
-
- }
- else {
- // set step size to maximal value
- gMC->SetMaxStep(kBig);
- }
-
- }
+ // Check that FRAME is there otherwise we have no place where to put the TRD
+ AliModule* frame = gAlice->GetModule("FRAME");
+ if (!frame) return;
- }
+ // Define the chambers
+ AliTRD::CreateGeometry();
}
//_____________________________________________________________________________
-Double_t AliTRDv2::BetheBloch(Double_t bg)
+void AliTRDv2::CreateMaterials()
{
//
- // Parametrization of the Bethe-Bloch-curve
- // The parametrization is the same as for the TPC and is taken from Lehrhaus.
+ // Create materials for the Transition Radiation Detector version 2
//
- // This parameters have been adjusted to averaged values from GEANT
- const Double_t kP1 = 7.17960e-02;
- const Double_t kP2 = 8.54196;
- const Double_t kP3 = 1.38065e-06;
- const Double_t kP4 = 5.30972;
- const Double_t kP5 = 2.83798;
-
- // This parameters have been adjusted to Xe-data found in:
- // Allison & Cobb, Ann. Rev. Nucl. Sci. (1980), 30, 253
- //const Double_t kP1 = 0.76176E-1;
- //const Double_t kP2 = 10.632;
- //const Double_t kP3 = 3.17983E-6;
- //const Double_t kP4 = 1.8631;
- //const Double_t kP5 = 1.9479;
-
- if (bg > 0) {
- Double_t yy = bg / TMath::Sqrt(1. + bg*bg);
- Double_t aa = TMath::Power(yy,kP4);
- Double_t bb = TMath::Power((1./bg),kP5);
- bb = TMath::Log(kP3 + bb);
- return ((kP2 - aa - bb)*kP1 / aa);
- }
- else
- return 0;
+ AliTRD::CreateMaterials();
}
-//_____________________________________________________________________________
-Double_t Ermilova(Double_t *x, Double_t *)
-{
- //
- // Calculates the delta-ray energy distribution according to Ermilova.
- // Logarithmic scale !
- //
-
- Double_t energy;
- Double_t dpos;
- Double_t dnde;
-
- Int_t pos1, pos2;
-
- const Int_t nV = 31;
-
- Float_t vxe[nV] = { 2.3026, 2.9957, 3.4012, 3.6889, 3.9120
- , 4.0943, 4.2485, 4.3820, 4.4998, 4.6052
- , 4.7005, 5.0752, 5.2983, 5.7038, 5.9915
- , 6.2146, 6.5221, 6.9078, 7.3132, 7.6009
- , 8.0064, 8.5172, 8.6995, 8.9872, 9.2103
- , 9.4727, 9.9035,10.3735,10.5966,10.8198
- ,11.5129 };
-
- Float_t vye[nV] = { 80.0 , 31.0 , 23.3 , 21.1 , 21.0
- , 20.9 , 20.8 , 20.0 , 16.0 , 11.0
- , 8.0 , 6.0 , 5.2 , 4.6 , 4.0
- , 3.5 , 3.0 , 1.4 , 0.67 , 0.44
- , 0.3 , 0.18 , 0.12 , 0.08 , 0.056
- , 0.04 , 0.023, 0.015, 0.011, 0.01
- , 0.004 };
-
- energy = x[0];
-
- // Find the position
- pos1 = pos2 = 0;
- dpos = 0;
- do {
- dpos = energy - vxe[pos2++];
- }
- while (dpos > 0);
- pos2--;
- if (pos2 > nV) pos2 = nV;
- pos1 = pos2 - 1;
-
- // Differentiate between the sampling points
- dnde = (vye[pos1] - vye[pos2]) / (vxe[pos2] - vxe[pos1]);
-
- return dnde;
-
-}
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff