More precise response function of the RICH has been introduced to calculate probabili...

[u/mrichter/AliRoot.git] / TRD / AliTRD.cxx

/**************************************************************************
 * 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                                            //
//  This class contains the basic functions for the Transition Radiation     //
//  Detector.                                                                //
//                                                                           //
///////////////////////////////////////////////////////////////////////////////

#include <stdlib.h>
#include <Riostream.h>

#include <TFile.h>
#include <TGeometry.h>
#include <TLorentzVector.h>
#include <TMath.h>
#include <TNode.h>
#include <TPGON.h> 
#include <TParticle.h>
#include <TROOT.h>
#include <TTree.h>
#include <TVirtualMC.h>
 
#include "AliConst.h"
#include "AliDigit.h"
#include "AliLoader.h"
#include "AliMagF.h"
#include "AliRun.h"
#include "AliTRD.h"
#include "AliTRDdigit.h"
#include "AliTRDdigitizer.h"
#include "AliTRDdigitsManager.h"
#include "AliTRDgeometryFull.h"
#include "AliTRDhit.h"
#include "AliTRDpoints.h"
#include "AliTRDrawData.h"
#include "AliTrackReference.h"
#include "AliMC.h"

ClassImp(AliTRD)
 
//_____________________________________________________________________________
AliTRD::AliTRD()
{
  //
  // Default constructor
  //

  fIshunt        = 0;
  fGasMix        = 0;
  fHits          = 0;
  fDigits        = 0;

  fGeometry      = 0;

  fGasDensity    = 0;
  fFoilDensity   = 0;

  fDrawTR        = 0;
  fDisplayType   = 0;
 
}
 
//_____________________________________________________________________________
AliTRD::AliTRD(const char *name, const char *title)
       : AliDetector(name,title)
{
  //
  // Standard constructor for the TRD
  //

  // 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);
  } 

  // Define the TRD geometry
  if ((frame->IsVersion() == 0) ||
      (frame->IsVersion() == 1)) {
    fGeometry = new AliTRDgeometryFull();
  }
  else {
    Error("Ctor","Could not find valid FRAME version\n");
    exit(1);
  }

  // Save the geometry
  TDirectory* saveDir = gDirectory;
  gAlice->GetRunLoader()->CdGAFile();
  fGeometry->Write("TRDgeometry");
  saveDir->cd();

  // Allocate the hit array
  fHits           = new TClonesArray("AliTRDhit"     ,405);
  gAlice->GetMCApp()->AddHitList(fHits);

  // Allocate the digits array
  fDigits         = 0;

  fIshunt        = 0;
  fGasMix        = 1;

  fGasDensity    = 0;
  fFoilDensity   = 0;

  fDrawTR        = 0;
  fDisplayType   = 0;

  SetMarkerColor(kWhite);   

}

//_____________________________________________________________________________
AliTRD::AliTRD(const AliTRD &trd):AliDetector(trd)
{
  //
  // Copy constructor
  //

  ((AliTRD &) trd).Copy(*this);

}

//_____________________________________________________________________________
AliTRD::~AliTRD()
{
  //
  // TRD destructor
  //

  fIshunt = 0;

  if (fGeometry) {
    delete fGeometry;
    fGeometry  = 0;
  }
  if (fHits) {
    delete fHits;
    fHits      = 0;
  }

}

//_____________________________________________________________________________
void AliTRD::Hits2Digits()
{
  //
  // Create digits
  //
  AliTRDdigitizer digitizer("TRDdigitizer","TRD digitizer class");
  digitizer.SetDebug(GetDebug());
  
  // Initialization
  digitizer.InitDetector();
    
  if (!fLoader->TreeH()) fLoader->LoadHits("read");
  fLoader->LoadDigits("recreate");
  AliRunLoader* runLoader = fLoader->GetRunLoader(); 

  for (Int_t iEvent = 0; iEvent < runLoader->GetNumberOfEvents(); iEvent++) {
    digitizer.Open(runLoader->GetFileName().Data(), iEvent);
    digitizer.MakeDigits();
    digitizer.WriteDigits();
  }

  fLoader->UnloadHits();
  fLoader->UnloadDigits();

}

//_____________________________________________________________________________
void AliTRD::Hits2SDigits()
{
  //
  // Create summable digits
  //

  AliTRDdigitizer digitizer("TRDdigitizer","TRD digitizer class");
  // For the summable digits
  digitizer.SetSDigits(kTRUE);
  digitizer.SetDebug(GetDebug());

  // Initialization
  digitizer.InitDetector();
    
  if (!fLoader->TreeH()) fLoader->LoadHits("read");
  fLoader->LoadSDigits("recreate");
  AliRunLoader* runLoader = fLoader->GetRunLoader(); 

  for (Int_t iEvent = 0; iEvent < runLoader->GetNumberOfEvents(); iEvent++) {
    digitizer.Open(runLoader->GetFileName().Data(), iEvent);
    digitizer.MakeDigits();
    digitizer.WriteDigits();
  }

  fLoader->UnloadHits();
  fLoader->UnloadSDigits();
  
}

//_____________________________________________________________________________
AliDigitizer* AliTRD::CreateDigitizer(AliRunDigitizer* manager) const
{
  //
  // Creates a new digitizer object
  //

  return new AliTRDdigitizer(manager);

}

//_____________________________________________________________________________
void AliTRD::SDigits2Digits()
{
  //
  // Create final digits from summable digits
  //

   // Create the TRD digitizer
  AliTRDdigitizer digitizer("TRDdigitizer","TRD digitizer class");  
  digitizer.SetDebug(GetDebug());

  // Set the parameter
  digitizer.SetEvent(gAlice->GetEvNumber());

  // Initialization
  digitizer.InitDetector();

  // Read the s-digits via digits manager
  AliTRDdigitsManager sdigitsManager;
 
  sdigitsManager.SetDebug(GetDebug());
  sdigitsManager.SetSDigits(kTRUE);
  sdigitsManager.CreateArrays();
  
  if (!fLoader->TreeS()) 
    if (fLoader->LoadSDigits("read"))
     {
       Error("SDigits2Digits","Error while reading SDigits for event %d",gAlice->GetEvNumber());
       return;
     }
  if (!fLoader->TreeS()) return;
  
  sdigitsManager.ReadDigits(fLoader->TreeS());

  // Add the s-digits to the input list 
  digitizer.AddSDigitsManager(&sdigitsManager);

  // Convert the s-digits to normal digits
  digitizer.SDigits2Digits();

  // Store the digits
  if (!fLoader->TreeD()) fLoader->MakeTree("D");
  if (digitizer.MakeBranch(fLoader->TreeD())){
    digitizer.WriteDigits();
  }

}

//_____________________________________________________________________________
void AliTRD::Digits2Raw() 
{
  //
  // convert digits of the current event to raw data
  //

  fLoader->LoadDigits();
  TTree* digits = fLoader->TreeD();
  if (!digits) {
    Error("Digits2Raw", "no digits tree");
    return;
  }

  AliTRDrawData rawWriter;
//  rawWriter.SetDebug(2);
  if (!rawWriter.Digits2Raw(digits)) {
    Error("AliTRD::Digits2Raw","The raw writer could not load the digits tree");
  }

  fLoader->UnloadDigits();

}

//_____________________________________________________________________________
void AliTRD::AddHit(Int_t track, Int_t det, Float_t *hits, Int_t q
                  , Bool_t inDrift)
{
  //
  // Add a hit for the TRD
  // 

  TClonesArray &lhits = *fHits;
  AliTRDhit *hit = new(lhits[fNhits++]) AliTRDhit(fIshunt,track,det,hits,q);
  if (inDrift) {
    hit->SetDrift();
  }
  else {
    hit->SetAmplification();
  }
  if (q < 0) {
    hit->SetTRphoton();
  }

}

//_____________________________________________________________________________
void AliTRD::BuildGeometry()
{
  //
  // Create the ROOT TNode geometry for the TRD
  //

  TNode *node, *top;
  TPGON *pgon;

  Float_t rmin, rmax;
  Float_t zmax1, zmax2;

  Int_t   iPlan;
 
  const Int_t kColorTRD = 46;
  
  // Find the top node alice
  top = gAlice->GetGeometry()->GetNode("alice");
  
  if      (fDisplayType == 0) {

    pgon = new TPGON("S_TRD","TRD","void",0,360,AliTRDgeometry::Nsect(),4);
    rmin = AliTRDgeometry::Rmin();
    rmax = AliTRDgeometry::Rmax();
    pgon->DefineSection(0,-AliTRDgeometry::Zmax1(),rmax,rmax);
    pgon->DefineSection(1,-AliTRDgeometry::Zmax2(),rmin,rmax);
    pgon->DefineSection(2, AliTRDgeometry::Zmax2(),rmin,rmax);
    pgon->DefineSection(3, AliTRDgeometry::Zmax1(),rmax,rmax);
    top->cd();
    node = new TNode("TRD","TRD","S_TRD",0,0,0,"");
    node->SetLineColor(kColorTRD);
    fNodes->Add(node);

  }
  else if (fDisplayType == 1) {

    Char_t name[7];

    Float_t slope = (AliTRDgeometry::Zmax1() - AliTRDgeometry::Zmax2())
                  / (AliTRDgeometry::Rmax()  - AliTRDgeometry::Rmin());

    rmin  = AliTRDgeometry::Rmin() + AliTRDgeometry::CraHght();
    rmax  = rmin                   + AliTRDgeometry::CdrHght();

    Float_t thickness = rmin - AliTRDgeometry::Rmin();
    zmax2 = AliTRDgeometry::Zmax2() + slope * thickness;
    zmax1 = zmax2 + slope * AliTRDgeometry::DrThick();

    for (iPlan = 0; iPlan < AliTRDgeometry::Nplan(); iPlan++) {

      sprintf(name,"S_TR1%d",iPlan);
      pgon  = new TPGON(name,"TRD","void",0,360,AliTRDgeometry::Nsect(),4);
      pgon->DefineSection(0,-zmax1,rmax,rmax);
      pgon->DefineSection(1,-zmax2,rmin,rmax);
      pgon->DefineSection(2, zmax2,rmin,rmax);
      pgon->DefineSection(3, zmax1,rmax,rmax);
      top->cd();
      node = new TNode("TRD","TRD",name,0,0,0,"");
      node->SetLineColor(kColorTRD);
      fNodes->Add(node);

      Float_t height = AliTRDgeometry::Cheight() + AliTRDgeometry::Cspace(); 
      rmin  = rmin  + height;
      rmax  = rmax  + height;
      zmax1 = zmax1 + slope * height;
      zmax2 = zmax2 + slope * height;

    }

    thickness += AliTRDgeometry::DrThick();
    rmin  = AliTRDgeometry::Rmin() + thickness;
    rmax  = rmin + AliTRDgeometry::AmThick();
    zmax2 = AliTRDgeometry::Zmax2() + slope * thickness;
    zmax1 = zmax2 + slope * AliTRDgeometry::AmThick();

    for (iPlan = 0; iPlan < AliTRDgeometry::Nplan(); iPlan++) {

      sprintf(name,"S_TR2%d",iPlan);
      pgon  = new TPGON(name,"TRD","void",0,360,AliTRDgeometry::Nsect(),4);
      pgon->DefineSection(0,-zmax1,rmax,rmax);
      pgon->DefineSection(1,-zmax2,rmin,rmax);
      pgon->DefineSection(2, zmax2,rmin,rmax);
      pgon->DefineSection(3, zmax1,rmax,rmax);
      top->cd();
      node = new TNode("TRD","TRD",name,0,0,0,"");
      node->SetLineColor(kColorTRD);
      fNodes->Add(node);

      Float_t height = AliTRDgeometry::Cheight() + AliTRDgeometry::Cspace(); 
      rmin  = rmin  + height;
      rmax  = rmax  + height;
      zmax1 = zmax1 + slope * height;
      zmax2 = zmax2 + slope * height;

    }

  }

}
 
//_____________________________________________________________________________
void AliTRD::Copy(TObject &trd) const
{
  //
  // Copy function
  //

  ((AliTRD &) trd).fGasMix      = fGasMix;
  ((AliTRD &) trd).fGeometry    = fGeometry;       
  ((AliTRD &) trd).fGasDensity  = fGasDensity;
  ((AliTRD &) trd).fFoilDensity = fFoilDensity;
  ((AliTRD &) trd).fDrawTR      = fDrawTR;
  ((AliTRD &) trd).fDisplayType = fDisplayType;

  //AliDetector::Copy(trd);

}

//_____________________________________________________________________________
void AliTRD::CreateGeometry()
{
  //
  // Creates the volumes for the TRD chambers
  //

  // Check that FRAME is there otherwise we have no place where to put the TRD
  AliModule* frame = gAlice->GetModule("FRAME");
  if (!frame) {
    printf(" The TRD needs the FRAME to be defined first\n");
    return;
  }

  fGeometry->CreateGeometry(fIdtmed->GetArray() - 1299);

}
 
//_____________________________________________________________________________
void AliTRD::CreateMaterials()
{
  //
  // Create the materials for the TRD
  // Origin Y.Foka
  //

  Int_t   isxfld = gAlice->Field()->Integ();
  Float_t sxmgmx = gAlice->Field()->Max();
  
  // For polyethilene (CH2) 
  Float_t ape[2] = { 12., 1. };
  Float_t zpe[2] = {  6., 1. };
  Float_t wpe[2] = {  1., 2. };
  Float_t dpe    = 0.95;

  // For mylar (C5H4O2) 
  Float_t amy[3] = { 12., 1., 16. };
  Float_t zmy[3] = {  6., 1.,  8. };
  Float_t wmy[3] = {  5., 4.,  2. };
  Float_t dmy    = 1.39;

  // For CO2 
  Float_t aco[2] = { 12., 16. };
  Float_t zco[2] = {  6.,  8. };
  Float_t wco[2] = {  1.,  2. };
  Float_t dco    = 0.001977;

  // For water
  Float_t awa[2] = {  1., 16. };
  Float_t zwa[2] = {  1.,  8. };
  Float_t wwa[2] = {  2.,  1. };
  Float_t dwa    = 1.0;

  // For isobutane (C4H10)
  Float_t ais[2] = { 12.,  1. };
  Float_t zis[2] = {  6.,  1. };
  Float_t wis[2] = {  4., 10. };
  Float_t dis    = 0.00267;

  // For plexiglas (C5H8O2)
  Float_t apg[3] = { 12.011 ,  1.0    , 15.9994 };
  Float_t zpg[3] = {  6.0   ,  1.0    ,  8.0    };
  Float_t wpg[3] = {  5.0   ,  8.0    ,  2.0    };
  Float_t dpg    = 1.18; 
  
  // For epoxy (C18H19O3)
  Float_t aEpoxy[3] = { 15.9994 ,  1.00794 , 12.0107 }; 
  Float_t zEpoxy[3] = {  8.0    ,  1.0     ,  6.0    }; 
  Float_t wEpoxy[3] = {  3.0    , 19.0     , 18.0    }; 
  Float_t dEpoxy    = 1.8 ; 

  // For air  
  Float_t aAir[4]   = { 12.0      , 14.0      , 16.0      , 36.0     };
  Float_t zAir[4]   = {  6.0      ,  7.0      ,  8.0      , 18.0     };
  Float_t wAir[4]   = {  0.000124 ,  0.755267 ,  0.231781 ,  0.012827};
  Float_t dAir      = 1.20479E-3;

  // For G10
  Float_t aG10[4]   = {  1.0         , 12.011       , 15.9994      , 28.086       };
  Float_t zG10[4]   = {  1.0         ,  6.0         ,  8.0         , 14.0         };
  //PH  Float_t wG10[4]   = {  0.148648649 ,  0.104054054 ,  0.483499056 ,  0.241666667 };
  Float_t wG10[4]={0.15201,0.10641,0.49444,0.24714};
  Float_t dG10      = 1.7;

  // For Xe/CO2-gas-mixture 
  Float_t aXeCO2[3] = { 39.948, 12.0107, 15.9994 };
  Float_t zXeCO2[3] = { 18.0,    6.0,     8.0    };
  Float_t wXeCO2[3] = {  0.85,   0.0375,  0.1125 };
  // Xe-content of the Xe/CO2-mixture (85% / 15%) 
  Float_t fxc    = .85;
  // Xe-content of the Xe/Isobutane-mixture (97% / 3%) 
  Float_t fxi    = .97;
  Float_t dxe    = .005858;
  
  // General tracking parameter
  Float_t tmaxfd = -10.;
  Float_t stemax = -1e10;
  Float_t deemax = -0.1;
  Float_t epsil  =  1e-4;
  Float_t stmin  = -0.001;
  
  Float_t absl, radl, d, buf[1];
  Float_t agm[2], zgm[2], wgm[2];
  Float_t dgm1, dgm2;
  Int_t   nbuf;
  
  //////////////////////////////////////////////////////////////////////////
  //     Define Materials 
  //////////////////////////////////////////////////////////////////////////

  AliMaterial( 1, "Al"   ,  26.98, 13.0, 2.7     ,     8.9 ,    37.2);
  //AliMaterial( 2, "Air"  ,  14.61,  7.3, 0.001205, 30420.0 , 67500.0);
  AliMaterial( 4, "Xe"   , 131.29, 54.0, dxe     ,  1447.59,     0.0);
  AliMaterial( 5, "Cu"   ,  63.54, 29.0, 8.96    ,     1.43,    14.8);
  AliMaterial( 6, "C"    ,  12.01,  6.0, 2.265   ,    18.8 ,    74.4);
  //AliMaterial(12, "G10"  ,  20.00, 10.0, 1.7     ,    19.4 ,   999.0);
  AliMaterial(15, "Sn"   , 118.71, 50.0, 7.31    ,     1.21,    14.8);
  AliMaterial(16, "Si"   ,  28.09, 14.0, 2.33    ,     9.36,    37.2);
  //AliMaterial(17, "Epoxy",  17.75,  8.9, 1.8     ,    21.82,   999.0);

  // Mixtures 
  AliMixture(2, "Air"         ,  aAir,  zAir,  dAir,  4,   wAir);
  AliMixture(3, "Polyethilene",   ape,   zpe,   dpe, -2,    wpe);
  AliMixture(7, "Mylar",          amy,   zmy,   dmy, -3,    wmy);
  AliMixture(8, "CO2",            aco,   zco,   dco, -2,    wco);
  AliMixture(9, "Isobutane",      ais,   zis,   dis, -2,    wis);
  AliMixture(12,"G10",           aG10,  zG10,  dG10,  4,   wG10);
  AliMixture(13,"Water",          awa,   zwa,   dwa, -2,    wwa);
  AliMixture(14,"Plexiglas",      apg,   zpg,   dpg, -3,    wpg);
  AliMixture(17,"Epoxy",       aEpoxy,zEpoxy,dEpoxy, -3, wEpoxy);

  // Gas mixtures
  Char_t namate[21]="";
  // Xe/CO2-mixture
  // Get properties of Xe 
  //gMC->Gfmate((*fIdmate)[4], namate, agm[0], zgm[0], d, radl, absl, buf, nbuf);
  // Get properties of CO2 
  //gMC->Gfmate((*fIdmate)[8], namate, agm[1], zgm[1], d, radl, absl, buf, nbuf);
  // Create gas mixture 
  wgm[0] = fxc;
  wgm[1] = 1. - fxc;
  dgm1   = wgm[0] * dxe + wgm[1] * dco;
  AliMixture(10, "Gas mixture 1", aXeCO2, zXeCO2, dgm1,  3, wXeCO2);

  // Xe/Isobutane-mixture
  // Get properties of Xe 
  gMC->Gfmate((*fIdmate)[4], namate, agm[0], zgm[0], d, radl, absl, buf, nbuf);
  // Get properties of Isobutane
  gMC->Gfmate((*fIdmate)[9], namate, agm[1], zgm[1], d, radl, absl, buf, nbuf);
  // Create gas mixture 
  wgm[0] = fxi;
  wgm[1] = 1. - fxi;
  dgm2   = wgm[0] * dxe + wgm[1] * dis;
  AliMixture(11, "Gas mixture 2", agm, zgm, dgm2,  2, wgm);
 
  //////////////////////////////////////////////////////////////////////////
  //     Tracking Media Parameters 
  //////////////////////////////////////////////////////////////////////////

  // Al Frame 
  AliMedium(1, "Al Frame",   1, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Air 
  AliMedium(2, "Air",        2, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Polyethilene 
  AliMedium(3, "Radiator",   3, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Xe 
  AliMedium(4, "Xe",         4, 1, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Cu pads 
  AliMedium(5, "Padplane",   5, 1, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Fee + cables 
  AliMedium(6, "Readout",    1, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // C frame 
  AliMedium(7, "C Frame",    6, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Mylar foils 
  AliMedium(8, "Mylar",      7, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  if (fGasMix == 1) {
    // Gas-mixture (Xe/CO2) 
    AliMedium(9, "Gas-mix",   10, 1, isxfld, sxmgmx
                  , tmaxfd, stemax, deemax, epsil, stmin);
  }
  else {
    // Gas-mixture (Xe/Isobutane) 
    AliMedium(9, "Gas-mix",   11, 1, isxfld, sxmgmx
                  , tmaxfd, stemax, deemax, epsil, stmin);
  }
  // Nomex-honeycomb (use carbon for the time being) 
  AliMedium(10, "Nomex",      6, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Kapton foils (use Mylar for the time being) 
  AliMedium(11, "Kapton",     7, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Gas-filling of the radiator 
  AliMedium(12, "CO2",        8, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // G10-plates
  AliMedium(13, "G10-plates",12, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Cooling water
  AliMedium(14, "Water",     13, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Rohacell (plexiglas) for the radiator
  AliMedium(15, "Rohacell",  14, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Al layer in MCMs
  AliMedium(16, "MCM-Al"  ,   1, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Sn layer in MCMs
  AliMedium(17, "MCM-Sn"  ,  15, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Cu layer in MCMs
  AliMedium(18, "MCM-Cu"  ,   5, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // G10 layer in MCMs
  AliMedium(19, "MCM-G10" ,  12, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Si in readout chips
  AliMedium(20, "Chip-Si" ,  16, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Epoxy in readout chips
  AliMedium(21, "Chip-Ep" ,  17, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // PE in connectors
  AliMedium(22, "Conn-PE" ,   3, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Cu in connectors
  AliMedium(23, "Chip-Cu" ,   5, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Al of cooling pipes
  AliMedium(24, "Cooling" ,   1, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);
  // Cu in services
  AliMedium(25, "Serv-Cu" ,   5, 0, isxfld, sxmgmx
                , tmaxfd, stemax, deemax, epsil, stmin);

  // Save the density values for the TRD absorbtion
  fFoilDensity = dmy;
  if (fGasMix == 1)
    fGasDensity = dgm1;
  else
    fGasDensity = dgm2;

}

//_____________________________________________________________________________
void AliTRD::DrawModule() const
{
  //
  // Draw a shaded view of the Transition Radiation Detector version 0
  //

  // Set everything unseen
  gMC->Gsatt("*"   ,"SEEN",-1);
  
  // Set ALIC mother transparent
  gMC->Gsatt("ALIC","SEEN", 0);
  
  // Set the volumes visible
  if (fGeometry->IsVersion() == 0) {
    gMC->Gsatt("B071","SEEN", 0);
    gMC->Gsatt("B074","SEEN", 0);
    gMC->Gsatt("B075","SEEN", 0);
    gMC->Gsatt("B077","SEEN", 0);
    gMC->Gsatt("BTR1","SEEN", 0);
    gMC->Gsatt("BTR2","SEEN", 0);
    gMC->Gsatt("BTR3","SEEN", 0);
    gMC->Gsatt("UTR1","SEEN", 0);
    gMC->Gsatt("UTR2","SEEN", 0);
    gMC->Gsatt("UTR3","SEEN", 0);
  }
  else {
    gMC->Gsatt("B071","SEEN", 0);
    gMC->Gsatt("B074","SEEN", 0);
    gMC->Gsatt("B075","SEEN", 0);
    gMC->Gsatt("B077","SEEN", 0);
    gMC->Gsatt("BTR1","SEEN", 0);
    gMC->Gsatt("BTR2","SEEN", 0);
    gMC->Gsatt("BTR3","SEEN", 0);
    gMC->Gsatt("UTR1","SEEN", 0);
    if (fGeometry->GetPHOShole())
      gMC->Gsatt("UTR2","SEEN", 0);
    if (fGeometry->GetRICHhole())
      gMC->Gsatt("UTR3","SEEN", 0);
  }
//   gMC->Gsatt("UCII","SEEN", 0);
//   gMC->Gsatt("UCIM","SEEN", 0);
//   gMC->Gsatt("UCIO","SEEN", 0);
//   gMC->Gsatt("UL02","SEEN", 1);
//   gMC->Gsatt("UL05","SEEN", 1);
//   gMC->Gsatt("UL06","SEEN", 1);
  
  gMC->Gdopt("hide", "on");
  gMC->Gdopt("shad", "on");
  gMC->Gsatt("*", "fill", 7);
  gMC->SetClipBox(".");
  gMC->SetClipBox("*", 0, 2000, -2000, 2000, -2000, 2000);
  gMC->DefaultRange();
  gMC->Gdraw("alic", 40, 30, 0, 12, 9.4, .021, .021);
  gMC->Gdhead(1111, "Transition Radiation Detector");
  gMC->Gdman(18, 4, "MAN");

}

//_____________________________________________________________________________
Int_t AliTRD::DistancetoPrimitive(Int_t , Int_t )
{
  //
  // Distance between the mouse and the TRD detector on the screen
  // Dummy routine
  
  return 9999;

}
 
//_____________________________________________________________________________
void AliTRD::Init()
{
  //
  // Initialize the TRD detector after the geometry has been created
  //

  Int_t i;

  if (fDebug) {
    printf("\n%s: ",ClassName());
    for (i = 0; i < 35; i++) printf("*");
    printf(" TRD_INIT ");
    for (i = 0; i < 35; i++) printf("*");
    printf("\n");
  }

  if (fGeometry->IsVersion() == 1) {
    printf("%s: Full geometry version initialized\n",ClassName());
    if (fGeometry->GetPHOShole())
      printf("%s: Leave space in front of PHOS free\n",ClassName());
    if (fGeometry->GetRICHhole())
      printf("%s: Leave space in front of RICH free\n",ClassName());
  }
  else {
    printf("%s: Not a valid geometry\n",ClassName());
  }
  
  if (fGasMix == 1) {
    printf("%s: Gas Mixture: 85%% Xe + 15%% CO2\n",ClassName());
  }
  else {
    printf("%s: Gas Mixture: 97%% Xe + 3%% Isobutane\n",ClassName());
  }

}

//_____________________________________________________________________________
void AliTRD::LoadPoints(Int_t )
{
  //
  // Store x, y, z of all hits in memory.
  // Hit originating from TR photons are given a different color
  //

  //if (!fDrawTR) {
  //  AliDetector::LoadPoints(track);
  //  return;
  //}

  if (fHits == 0) return;

  Int_t nhits = fHits->GetEntriesFast();
  if (nhits == 0) return;

  Int_t tracks = gAlice->GetMCApp()->GetNtrack();
  if (fPoints == 0) fPoints = new TObjArray(tracks);

  AliTRDhit *ahit;
  
  Int_t    *ntrkE = new Int_t[tracks];
  Int_t    *ntrkT = new Int_t[tracks];
  Int_t    *limiE = new Int_t[tracks];
  Int_t    *limiT = new Int_t[tracks];
  Float_t **coorE = new Float_t*[tracks];
  Float_t **coorT = new Float_t*[tracks];
  for(Int_t i = 0; i < tracks; i++) {
    ntrkE[i] = 0;
    ntrkT[i] = 0;
    coorE[i] = 0;
    coorT[i] = 0;
    limiE[i] = 0;
    limiT[i] = 0;
  }
  
  AliTRDpoints *points = 0;
  Float_t      *fp     = 0;
  Int_t         trk;
  Int_t         chunk  = nhits / 4 + 1;

  // Loop over all the hits and store their position
  ahit = (AliTRDhit *) FirstHit(-1);
  while (ahit) {

    // dEdx hits
    if (ahit->GetCharge() >= 0) {

      trk = ahit->GetTrack();
      if (ntrkE[trk] == limiE[trk]) {
        // Initialise a new track
        fp = new Float_t[3*(limiE[trk]+chunk)];
        if (coorE[trk]) {
          memcpy(fp,coorE[trk],sizeof(Float_t)*3*limiE[trk]);
          delete [] coorE[trk];
        }
        limiE[trk] += chunk;
        coorE[trk]  = fp;
      } 
      else {
        fp = coorE[trk];
      }
      fp[3*ntrkE[trk]  ] = ahit->X();
      fp[3*ntrkE[trk]+1] = ahit->Y();
      fp[3*ntrkE[trk]+2] = ahit->Z();
      ntrkE[trk]++;

    }
    // TR photon hits
    else if ((ahit->GetCharge() < 0) && (fDrawTR)) {

      trk = ahit->GetTrack();
      if (ntrkT[trk] == limiT[trk]) {
        // Initialise a new track
        fp = new Float_t[3*(limiT[trk]+chunk)];
        if (coorT[trk]) {
          memcpy(fp,coorT[trk],sizeof(Float_t)*3*limiT[trk]);
          delete [] coorT[trk];
        }
        limiT[trk] += chunk;
        coorT[trk]  = fp;
      } 
      else {
        fp = coorT[trk];
      }
      fp[3*ntrkT[trk]  ] = ahit->X();
      fp[3*ntrkT[trk]+1] = ahit->Y();
      fp[3*ntrkT[trk]+2] = ahit->Z();
      ntrkT[trk]++;

    }

    ahit = (AliTRDhit *) NextHit();

  }

  for (trk = 0; trk < tracks; ++trk) {

    if (ntrkE[trk] || ntrkT[trk]) {

      points = new AliTRDpoints();
      points->SetDetector(this);
      points->SetParticle(trk);

      // Set the dEdx points
      if (ntrkE[trk]) {
        points->SetMarkerColor(GetMarkerColor());
        points->SetMarkerSize(GetMarkerSize());
        points->SetPolyMarker(ntrkE[trk],coorE[trk],GetMarkerStyle());
        delete [] coorE[trk];
        coorE[trk] = 0;
      }

      // Set the TR photon points
      if (ntrkT[trk]) {
        points->SetTRpoints(ntrkT[trk],coorT[trk]);
        delete [] coorT[trk];
        coorT[trk] = 0;
      }

      fPoints->AddAt(points,trk);

    }

  }

  delete [] coorE;
  delete [] coorT;
  delete [] ntrkE;
  delete [] ntrkT;
  delete [] limiE;
  delete [] limiT;

}

//_____________________________________________________________________________
void AliTRD::MakeBranch(Option_t* option)
{
  //
  // Create Tree branches for the TRD digits.
  //

  Int_t  buffersize = 4000;
  Char_t branchname[15];
  sprintf(branchname,"%s",GetName());

  const char *cD = strstr(option,"D");

  AliDetector::MakeBranch(option);

  if (fDigits && gAlice->TreeD() && cD) {
    MakeBranchInTree(gAlice->TreeD(),branchname,&fDigits,buffersize,0);
  }	

}

//_____________________________________________________________________________
void AliTRD::ResetDigits()
{
  //
  // Reset number of digits and the digits array for this detector
  //

  fNdigits = 0;
  if (fDigits) fDigits->Clear();

}

//_____________________________________________________________________________
void AliTRD::SetTreeAddress()
{
  //
  // Set the branch addresses for the trees.
  //

  if ( fLoader->TreeH() && (fHits == 0x0)) {
    fHits = new TClonesArray("AliTRDhit",405);
  }
  AliDetector::SetTreeAddress();

}

//_____________________________________________________________________________
void AliTRD::SetGasMix(Int_t imix)
{
  //
  // Defines the gas mixture (imix=0:  Xe/Isobutane imix=1: Xe/CO2)
  //
  
  if ((imix < 0) || (imix > 1)) {
    printf("Wrong input value: %d\n",imix);
    printf("Use standard setting\n");
    fGasMix = 1;
    return;
  }

  fGasMix = imix;

}

//_____________________________________________________________________________
void AliTRD::SetPHOShole()
{
  //
  // Selects a geometry with a hole in front of the PHOS
  //

  fGeometry->SetPHOShole();

}

//_____________________________________________________________________________
void AliTRD::SetRICHhole()
{
  //
  // Selects a geometry with a hole in front of the RICH
  //

  fGeometry->SetRICHhole();

}

//_____________________________________________________________________________
AliTRD &AliTRD::operator=(const AliTRD &trd)
{
  //
  // Assignment operator
  //

  if (this != &trd) ((AliTRD &) trd).Copy(*this);
  return *this;

}