The present commit corresponds to an important change in the way the
[u/mrichter/AliRoot.git] / TRD / AliTRD.cxx
index 7449e26..9b2adbe 100644 (file)
  * provided "as is" without express or implied warranty.                  *
  **************************************************************************/
 
-/*
-$Log$
-Revision 1.14  1999/11/02 16:57:02  fca
-Avoid non ansi warnings on HP compilers
-
-Revision 1.13  1999/11/02 16:35:56  fca
-New version of TRD introduced
-
-Revision 1.12  1999/11/01 20:41:51  fca
-Added protections against using the wrong version of FRAME
-
-Revision 1.11  1999/09/29 09:24:34  fca
-Introduction of the Copyright and cvs Log
-
-*/
+/* $Id$ */
 
 ///////////////////////////////////////////////////////////////////////////////
 //                                                                           //
 //  Transition Radiation Detector                                            //
 //  This class contains the basic functions for the Transition Radiation     //
-//  Detector, as well as the geometry.                                       //
-//  Functions specific to one particular geometry are contained in the       // 
-//  derived classes.                                                         //
-//                                                                           //
-//Begin_Html
-/*
-<img src="picts/AliTRDClass.gif">
-*/
-//End_Html
-//                                                                           //
+//  Detector.                                                                //
 //                                                                           //
 ///////////////////////////////////////////////////////////////////////////////
 
-#include <stdlib.h>
-
-#include <TMath.h>
-#include <TNode.h>
-#include <TPGON.h> 
+#include <TGeoGlobalMagField.h>
+#include <TVirtualMC.h>
+#include "AliMC.h"
+#include "AliMagF.h"
+#include "AliRun.h"
 
 #include "AliTRD.h"
-#include "AliRun.h"
-#include "AliConst.h"
+#include "AliTRDdigitizer.h"
+#include "AliTRDdigitsManager.h"
+#include "AliTRDgeometry.h"
+#include "AliTRDhit.h"
+#include "AliTRDrawData.h"
+#include "AliTRDSimParam.h"
+
 ClassImp(AliTRD)
  
 //_____________________________________________________________________________
 AliTRD::AliTRD()
+  :AliDetector()
+  ,fGeometry(0)
+  ,fGasDensity(0)
+  ,fFoilDensity(0)
+  ,fGasNobleFraction(0)
 {
   //
   // Default constructor
   //
-
-  Int_t iplan;
-
-  fIshunt      = 0;
-  fGasMix      = 0;
-  fHits        = 0;
-  fDigits      = 0;
-  fHole        = 0;
-
-  fClusters    = 0;
-  fNclusters   = 0;
-
-  // The chamber dimensions
-  for (iplan = 0; iplan < kNplan; iplan++) {
-    fClengthI[iplan]  = 0.;
-    fClengthM1[iplan] = 0.;
-    fClengthM2[iplan] = 0.;
-    fClengthO1[iplan] = 0.;
-    fClengthO2[iplan] = 0.;
-    fClengthO3[iplan] = 0.;
-    fCwidth[iplan]    = 0.;
-  }
-
-  for (iplan = 0; iplan < kNplan; iplan++) {
-    for (Int_t icham = 0; icham < kNcham; icham++) {
-      for (Int_t isect = 0; isect < kNsect; isect++) {
-        fRowMax[iplan][icham][isect] = 0;
-      }
-    }
-    fColMax[iplan] = 0;
-  }
-  fTimeMax       = 0;
-
-  fRowPadSize    = 0;
-  fColPadSize    = 0;
-  fTimeBinSize   = 0;
-
 }
  
 //_____________________________________________________________________________
 AliTRD::AliTRD(const char *name, const char *title)
-       : AliDetector(name,title)
+  :AliDetector(name,title)
+  ,fGeometry(0)
+  ,fGasDensity(0)
+  ,fFoilDensity(0)
+  ,fGasNobleFraction(0)
 {
   //
   // Standard constructor for the TRD
   //
 
-  Int_t iplan;
-
-  // 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");
+  // Check that FRAME is there otherwise we have no place where to put TRD
+  AliModule *frame = gAlice->GetModule("FRAME");
+  if (!frame) {
+    AliError("TRD needs FRAME to be present\n");
     exit(1);
   } 
 
-  // Define the TRD geometry according to the FRAME geometry
-  if (FRAME->IsVersion() == 0) 
-    // With hole
-    fHole = 1;
-  else 
-    // Without hole
-    fHole = 0; 
-
-  // Allocate the hit array
-  fHits      = new TClonesArray("AliTRDhit"    ,  405);
-
-  // Allocate the digits array
-  fDigits    = new TClonesArray("AliTRDdigit"  ,10000);
-
-  // Allocate the cluster array
-  fClusters  = new TClonesArray("AliTRDcluster",  400);
-  fNclusters = 0;
-   
-  fIshunt = 0;
-  fGasMix = 0;
-
-  // The chamber dimensions
-  for (iplan = 0; iplan < kNplan; iplan++) {
-    fClengthI[iplan]  = 0.;
-    fClengthM1[iplan] = 0.;
-    fClengthM2[iplan] = 0.;
-    fClengthO1[iplan] = 0.;
-    fClengthO2[iplan] = 0.;
-    fClengthO3[iplan] = 0.;
-    fCwidth[iplan]    = 0.;
+  // Define the TRD geometry
+  if ((frame->IsVersion() == 0) ||
+      (frame->IsVersion() == 1)) {
+    fGeometry = new AliTRDgeometry();
   }
-  
-  for (iplan = 0; iplan < kNplan; iplan++) {
-    for (Int_t icham = 0; icham < kNcham; icham++) {
-      for (Int_t isect = 0; isect < kNsect; isect++) {
-        fRowMax[iplan][icham][isect] = 0;
-      }
-    }
-    fColMax[iplan] = 0;
+  else {
+    AliError("Could not find valid FRAME version\n");
+    exit(1);
   }
-  fTimeMax       = 0;
-
-  fRowPadSize    = 0;
-  fColPadSize    = 0;
-  fTimeBinSize   = 0;
 
-  SetMarkerColor(kWhite);   
+  // Allocate the hit array
+  fHits = new TClonesArray("AliTRDhit",405);
+  gAlice->GetMCApp()->AddHitList(fHits);
 
 }
 
@@ -178,815 +96,420 @@ AliTRD::~AliTRD()
   // TRD destructor
   //
 
-  fIshunt = 0;
+  if (fGeometry) {
+    delete fGeometry;
+    fGeometry = 0;
+  }
 
-  delete fHits;
-  delete fDigits;
-  delete fClusters;
+  if (fHits) {
+    delete fHits;
+    fHits     = 0;
+  }
 
 }
 
 //_____________________________________________________________________________
-void AliTRD::AddCluster(Int_t *tracks, Int_t *clusters, Float_t *position)
+void AliTRD::Hits2Digits()
 {
   //
-  // Add a cluster for the TRD
-  // 
+  // Create digits
+  //
+
+  AliTRDdigitizer digitizer("TRDdigitizer","TRD digitizer class");
+  AliLog::SetClassDebugLevel("TRDdigitizer",AliDebugLevel());
 
-  TClonesArray &lclusters = *fClusters;
-  new(lclusters[fNclusters++]) AliTRDcluster(tracks,clusters,position);
+  // 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++) {
+    runLoader->GetEvent(iEvent);
+    digitizer.Open(runLoader,iEvent);
+    digitizer.MakeDigits();
+    digitizer.WriteDigits();
+  }
+
+  fLoader->UnloadHits();
+  fLoader->UnloadDigits();
 
 }
 
 //_____________________________________________________________________________
-void AliTRD::AddDigit(Int_t *tracks, Int_t *digits)
+void AliTRD::Hits2SDigits()
 {
   //
-  // Add a digit for the TRD
+  // Create summable digits
   //
 
-  TClonesArray &ldigits = *fDigits;
-  new(ldigits[fNdigits++]) AliTRDdigit(tracks,digits);
+  AliTRDdigitizer digitizer("TRDdigitizer","TRD digitizer class");
+  // For the summable digits
+  digitizer.SetSDigits(kTRUE);
+  AliLog::SetClassDebugLevel("TRDdigitizer",AliDebugLevel());
 
+  // 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++) {
+    runLoader->GetEvent(iEvent);
+    digitizer.Open(runLoader,iEvent);
+    digitizer.MakeDigits();
+    digitizer.WriteDigits();
+  }
+
+  fLoader->UnloadHits();
+  fLoader->UnloadSDigits();
+  
 }
 
 //_____________________________________________________________________________
-void AliTRD::AddHit(Int_t track, Int_t *vol, Float_t *hits)
+AliDigitizer *AliTRD::CreateDigitizer(AliRunDigitizer *manager) const
 {
   //
-  // Add a hit for the TRD
+  // Creates a new digitizer object
   //
 
-  TClonesArray &lhits = *fHits;
-  new(lhits[fNhits++]) AliTRDhit(fIshunt,track,vol,hits);
+  return new AliTRDdigitizer(manager);
 
 }
 
 //_____________________________________________________________________________
-void AliTRD::BuildGeometry()
+void AliTRD::SDigits2Digits()
 {
   //
-  // Create the ROOT TNode geometry for the TRD
+  // Create final digits from summable digits
   //
 
-  TNode *Node, *Top;
-  TPGON *pgon;
-  const Int_t kColorTRD = 46;
+  // Create the TRD digitizer
+  AliTRDdigitizer digitizer("TRDdigitizer","TRD digitizer class");  
+  AliLog::SetClassDebugLevel("TRDdigitizer",AliDebugLevel());
+
+  // Set the parameter
+  digitizer.SetEvent(gAlice->GetEvNumber());
+
+  // Initialization
+  digitizer.InitDetector();
+
+  // Read the s-digits via digits manager
+  AliTRDdigitsManager sdigitsManager;
+  AliLog::SetClassDebugLevel("TRDdigitisManager",AliDebugLevel());
+  sdigitsManager.SetSDigits(kTRUE);
+  sdigitsManager.CreateArrays();
   
-  // Find the top node alice
-  Top = gAlice->GetGeometry()->GetNode("alice");
+  if (!fLoader->TreeS()) { 
+    if (fLoader->LoadSDigits("read")) {
+      return;
+    }
+  }
+  if (!fLoader->TreeS()) {
+    AliError(Form("Error while reading SDigits for event %d",gAlice->GetEvNumber()));
+    return;
+  }
   
-  pgon = new TPGON("S_TRD","TRD","void",0,360,kNsect,4);
-  Float_t ff    = TMath::Cos(kDegrad * 180 / kNsect);
-  Float_t rrmin = kRmin / ff;
-  Float_t rrmax = kRmax / ff;
-  pgon->DefineSection(0,-kZmax1,rrmax,rrmax);
-  pgon->DefineSection(1,-kZmax2,rrmin,rrmax);
-  pgon->DefineSection(2, kZmax2,rrmin,rrmax);
-  pgon->DefineSection(3, kZmax1,rrmax,rrmax);
-  Top->cd();
-  Node = new TNode("TRD","TRD","S_TRD",0,0,0,"");
-  Node->SetLineColor(kColorTRD);
-  fNodes->Add(Node);
+  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::CreateGeometry()
+void AliTRD::Digits2Raw() 
 {
   //
-  // Creates the volumes for the TRD chambers
-  //
-  // Author: Christoph Blume (C.Blume@gsi.de) 20/07/99
-  //
-  // The volumes:
-  //    TRD1-3     (Air)   --- The TRD mother volumes for one sector. 
-  //                           To be placed into the spaceframe.
-  //
-  //    UAFI(/M/O) (Al)    --- The aluminum frame of the inner(/middle/outer) chambers (readout)
-  //    UCFI(/M/O) (C)     --- The carbon frame of the inner(/middle/outer) chambers 
-  //                           (driftchamber + radiator)
-  //    UAII(/M/O) (Air)   --- The inner part of the readout of the inner(/middle/outer) chambers
-  //    UFII(/M/O) (Air)   --- The inner part of the chamner and radiator of the 
-  //                           inner(/middle/outer) chambers
+  // Convert digits of the current event to raw data
   //
-  // The material layers in one chamber:
-  //    UL01       (G10)   --- The gas seal of the radiator
-  //    UL02       (CO2)   --- The gas in the radiator
-  //    UL03       (PE)    --- The foil stack
-  //    UL04       (Mylar) --- Entrance window to the driftvolume and HV-cathode
-  //    UL05       (Xe)    --- The driftvolume
-  //    UL06       (Xe)    --- The amplification region
-  //    
-  //    UL07       (Cu)    --- The pad plane
-  //    UL08       (G10)   --- The Nomex honeycomb support structure
-  //    UL09       (Cu)    --- FEE and signal lines
-  //    UL10       (PE)    --- The cooling devices
-  //    UL11       (Water) --- The cooling water
-
-  // Check that FRAME is there otherwise we have no place where to put the TRD
-  AliModule* FRAME = gAlice->GetModule("FRAME");
-  if (!FRAME) return;
-
-  Int_t iplan;
-
-  const Int_t npar_trd = 4;
-  const Int_t npar_cha = 3;
-
-  Float_t par_dum[3];
-  Float_t par_trd[npar_trd];
-  Float_t par_cha[npar_cha];
-
-  Float_t xpos, ypos, zpos;
-
-  Int_t *idtmed = fIdtmed->GetArray() - 1299;
-
-  // The length of the inner chambers
-  for (iplan = 0; iplan < kNplan; iplan++) 
-    fClengthI[iplan] = 110.0;
-
-  // The length of the middle chambers
-  fClengthM1[0] = 123.5;
-  fClengthM1[1] = 131.0;
-  fClengthM1[2] = 138.5;
-  fClengthM1[3] = 146.0;
-  fClengthM1[4] = 153.0;
-  fClengthM1[5] = 160.5;
-
-  fClengthM2[0] = 123.5 - 7.0;
-  fClengthM2[1] = 131.0 - 7.0;
-  fClengthM2[2] = 138.5 - 7.0;
-  fClengthM2[3] = 146.0 - 7.0;
-  fClengthM2[4] = 153.0 - 7.0;
-  fClengthM2[5] = 160.4 - 7.0;
-
-  // The length of the outer chambers
-  fClengthO1[0] = 123.5;
-  fClengthO1[1] = 131.0;
-  fClengthO1[2] = 134.5;
-  fClengthO1[3] = 142.0;
-  fClengthO1[4] = 142.0;
-  fClengthO1[5] = 134.5;
-
-  fClengthO2[0] = 123.5;
-  fClengthO2[1] = 131.0;
-  fClengthO2[2] = 134.5;
-  fClengthO2[3] = 142.0;
-  fClengthO2[4] = 142.0;
-  fClengthO2[5] = 134.5;
-
-  fClengthO3[0] =  86.5;
-  fClengthO3[1] = 101.5;
-  fClengthO3[2] = 112.5;
-  fClengthO3[3] = 127.5;
-  fClengthO3[4] = 134.5;
-  fClengthO3[5] = 134.5;
-
-  // The width of the chambers
-  fCwidth[0]    =  99.6;
-  fCwidth[1]    = 104.1;
-  fCwidth[2]    = 108.5;
-  fCwidth[3]    = 112.9;
-  fCwidth[4]    = 117.4;
-  fCwidth[5]    = 121.8;
-
-  // The TRD mother volume for one sector (Air) (dimensions identical to BTR1)
-  par_trd[0] = kSwidth1/2.;
-  par_trd[1] = kSwidth2/2.;
-  par_trd[2] = kSlenTR1/2.;
-  par_trd[3] = kSheight/2.;
-  gMC->Gsvolu("TRD1","TRD1",idtmed[1302-1],par_trd,npar_trd);
-  
-  // The TRD mother volume for one sector (Air) (dimensions identical to BTR2 + BTR3).
-  // Only used for the geometry with holes.
-  if (fHole) {
-
-    par_trd[0] = kSwidth1/2.;
-    par_trd[1] = kSwidth2/2.;
-    par_trd[2] = kSlenTR2/2.;
-    par_trd[3] = kSheight/2.;
-    gMC->Gsvolu("TRD2","TRD1",idtmed[1302-1],par_trd,npar_trd);
-
-    par_trd[0] = kSwidth1/2.;
-    par_trd[1] = kSwidth2/2.;
-    par_trd[2] = kSlenTR3/2.;
-    par_trd[3] = kSheight/2.;
-    gMC->Gsvolu("TRD3","TRD1",idtmed[1302-1],par_trd,npar_trd);
 
+  fLoader->LoadDigits();
+  TTree *digits = fLoader->TreeD();
+  if (!digits) {
+    AliError("No digits tree");
+    return;
   }
 
-  // The aluminum frames - readout + electronics (Al)
-  // The inner chambers
-  gMC->Gsvolu("UAFI","BOX ",idtmed[1301-1],par_dum,0);
-  // The middle chambers
-  gMC->Gsvolu("UAFM","BOX ",idtmed[1301-1],par_dum,0);
-  // The outer chambers
-  gMC->Gsvolu("UAFO","BOX ",idtmed[1301-1],par_dum,0);
-
-  // The inner part of the aluminum frames (Air)
-  // The inner chambers
-  gMC->Gsvolu("UAII","BOX ",idtmed[1302-1],par_dum,0);
-  // The middle chambers
-  gMC->Gsvolu("UAIM","BOX ",idtmed[1302-1],par_dum,0);
-  // The outer chambers
-  gMC->Gsvolu("UAIO","BOX ",idtmed[1302-1],par_dum,0);
-
-  // The carbon frames - radiator + driftchamber (C)
-  // The inner chambers
-  gMC->Gsvolu("UCFI","BOX ",idtmed[1307-1],par_dum,0);
-  // The middle chambers
-  gMC->Gsvolu("UCFM","BOX ",idtmed[1307-1],par_dum,0);
-  // The outer chambers
-  gMC->Gsvolu("UCFO","BOX ",idtmed[1307-1],par_dum,0);
-
-  // The inner part of the carbon frames (Air)
-  // The inner chambers
-  gMC->Gsvolu("UCII","BOX ",idtmed[1302-1],par_dum,0);
-  // The middle chambers
-  gMC->Gsvolu("UCIM","BOX ",idtmed[1302-1],par_dum,0);
-  // The outer chambers
-  gMC->Gsvolu("UCIO","BOX ",idtmed[1302-1],par_dum,0);
-
-  // The material layers inside the chambers
-  par_cha[0] = -1.;
-  par_cha[1] = -1.;
-  // G10 layer (radiator seal)
-  par_cha[2] = kSeThick/2;
-  gMC->Gsvolu("UL01","BOX ",idtmed[1313-1],par_cha,npar_cha);
-  // CO2 layer (radiator)
-  par_cha[2] = kRaThick/2;
-  gMC->Gsvolu("UL02","BOX ",idtmed[1312-1],par_cha,npar_cha);
-  // PE layer (radiator)
-  par_cha[2] = kPeThick/2;
-  gMC->Gsvolu("UL03","BOX ",idtmed[1303-1],par_cha,npar_cha);
-  // Mylar layer (entrance window + HV cathode) 
-  par_cha[2] = kMyThick/2;
-  gMC->Gsvolu("UL04","BOX ",idtmed[1308-1],par_cha,npar_cha);
-  // Xe/Isobutane layer (drift volume, sensitive) 
-  par_cha[2] = kDrThick/2.;
-  gMC->Gsvolu("UL05","BOX ",idtmed[1309-1],par_cha,npar_cha);
-  // Xe/Isobutane layer (amplification volume, not sensitive)
-  par_cha[2] = kAmThick/2.;
-  gMC->Gsvolu("UL06","BOX ",idtmed[1309-1],par_cha,npar_cha);
-  
-  // Cu layer (pad plane)
-  par_cha[2] = kCuThick/2;
-  gMC->Gsvolu("UL07","BOX ",idtmed[1305-1],par_cha,npar_cha);
-  // G10 layer (support structure)
-  par_cha[2] = kSuThick/2;
-  gMC->Gsvolu("UL08","BOX ",idtmed[1313-1],par_cha,npar_cha);
-  // Cu layer (FEE + signal lines)
-  par_cha[2] = kFeThick/2;
-  gMC->Gsvolu("UL09","BOX ",idtmed[1305-1],par_cha,npar_cha);
-  // PE layer (cooling devices)
-  par_cha[2] = kCoThick/2;
-  gMC->Gsvolu("UL10","BOX ",idtmed[1303-1],par_cha,npar_cha);
-  // Water layer (cooling)
-  par_cha[2] = kWaThick/2;
-  gMC->Gsvolu("UL11","BOX ",idtmed[1314-1],par_cha,npar_cha);
-
-  // Position the layers in the chambers
-  xpos = 0;
-  ypos = 0;
-
-  // G10 layer (radiator seal)
-  zpos = kSeZpos;
-  gMC->Gspos("UL01",1,"UCII",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL01",2,"UCIM",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL01",3,"UCIO",xpos,ypos,zpos,0,"ONLY");
-  // CO2 layer (radiator)
-  zpos = kRaZpos;
-  gMC->Gspos("UL02",1,"UCII",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL02",2,"UCIM",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL02",3,"UCIO",xpos,ypos,zpos,0,"ONLY");
-  // PE layer (radiator)
-  zpos = 0;
-  gMC->Gspos("UL03",1,"UL02",xpos,ypos,zpos,0,"ONLY");
-  // Mylar layer (entrance window + HV cathode)   
-  zpos = kMyZpos;
-  gMC->Gspos("UL04",1,"UCII",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL04",2,"UCIM",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL04",3,"UCIO",xpos,ypos,zpos,0,"ONLY");
-  // Xe/Isobutane layer (drift volume) 
-  zpos = kDrZpos;
-  gMC->Gspos("UL05",1,"UCII",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL05",2,"UCIM",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL05",3,"UCIO",xpos,ypos,zpos,0,"ONLY");
-  // Xe/Isobutane layer (amplification volume)
-  zpos = kAmZpos;
-  gMC->Gspos("UL06",1,"UCII",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL06",2,"UCIM",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL06",3,"UCIO",xpos,ypos,zpos,0,"ONLY");
-
-  // Cu layer (pad plane)
-  zpos = kCuZpos;
-  gMC->Gspos("UL07",1,"UAII",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL07",2,"UAIM",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL07",3,"UAIO",xpos,ypos,zpos,0,"ONLY");
-  // G10 layer (support structure)
-  zpos = kSuZpos;
-  gMC->Gspos("UL08",1,"UAII",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL08",2,"UAIM",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL08",3,"UAIO",xpos,ypos,zpos,0,"ONLY");
-  // Cu layer (FEE + signal lines)
-  zpos = kFeZpos; 
-  gMC->Gspos("UL09",1,"UAII",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL09",2,"UAIM",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL09",3,"UAIO",xpos,ypos,zpos,0,"ONLY");
-  // PE layer (cooling devices)
-  zpos = kCoZpos;
-  gMC->Gspos("UL10",1,"UAII",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL10",2,"UAIM",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL10",3,"UAIO",xpos,ypos,zpos,0,"ONLY");
-  // Water layer (cooling)
-  zpos = kWaZpos;
-  gMC->Gspos("UL11",1,"UAII",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL11",1,"UAIM",xpos,ypos,zpos,0,"ONLY");
-  gMC->Gspos("UL11",1,"UAIO",xpos,ypos,zpos,0,"ONLY");
-
-  // Position the chambers in the TRD mother volume
-  for (iplan = 1; iplan <= kNplan; iplan++) {
-
-    // The inner chambers ---------------------------------------------------------------
-
-    // the aluminum frame
-    par_cha[0] = fCwidth[iplan-1]/2.;
-    par_cha[1] = fClengthI[iplan-1]/2.;
-    par_cha[2] = kCaframe/2.;
-    xpos       = 0.;
-    ypos       = 0.;
-    zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UAFI",iplan       ,"TRD1",xpos,ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-    // the inner part of the aluminum frame
-    par_cha[0] = fCwidth[iplan-1]/2.   - kCathick;
-    par_cha[1] = fClengthI[iplan-1]/2. - kCathick;
-    par_cha[2] = kCaframe/2.;
-    xpos       = 0.;
-    ypos       = 0.;
-    zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UAII",iplan       ,"TRD1",xpos,ypos,zpos,0,"ONLY",par_cha,npar_cha);
-
-    // the carbon frame
-    par_cha[0] = fCwidth[iplan-1]/2.;
-    par_cha[1] = fClengthI[iplan-1]/2.;
-    par_cha[2] = kCcframe/2.;
-    xpos       = 0.;
-    ypos       = 0.;
-    zpos       = kCcframe/2.            - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UCFI",iplan       ,"TRD1",xpos,ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-    // the inner part of the carbon frame
-    par_cha[0] = fCwidth[iplan-1]/2.   - kCcthick;
-    par_cha[1] = fClengthI[iplan-1]/2. - kCcthick;
-    par_cha[2] = kCcframe/2.;
-    xpos       = 0.;
-    ypos       = 0.;
-    zpos       = kCcframe/2.            - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UCII",iplan       ,"TRD1",xpos,ypos,zpos,0,"ONLY",par_cha,npar_cha);
-
-    // The middle chambers --------------------------------------------------------------
-
-    // the aluminum frame
-    par_cha[0] = fCwidth[iplan-1]/2.;
-    par_cha[1] = fClengthM1[iplan-1]/2.;
-    par_cha[2] = kCaframe/2.;
-    xpos       = 0.;
-    ypos       = fClengthI[iplan-1]/2.  + fClengthM1[iplan-1]/2.;
-    zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UAFM",iplan         ,"TRD1",xpos, ypos,zpos,0,"MANY",par_cha,npar_cha);
-    gMC->Gsposp("UAFM",iplan+  kNplan,"TRD1",xpos,-ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-    // the inner part of the aluminum frame
-    par_cha[0] = fCwidth[iplan-1]/2.    - kCathick;
-    par_cha[1] = fClengthM1[iplan-1]/2. - kCathick;
-    par_cha[2] = kCaframe/2.;
-    xpos       = 0.;
-    ypos       = fClengthI[iplan-1]/2.  + fClengthM1[iplan-1]/2.;
-    zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UAIM",iplan         ,"TRD1",xpos, ypos,zpos,0,"ONLY",par_cha,npar_cha);
-    gMC->Gsposp("UAIM",iplan+  kNplan,"TRD1",xpos,-ypos,zpos,0,"ONLY",par_cha,npar_cha);
-
-    // the carbon frame
-    par_cha[0] = fCwidth[iplan-1]/2.;
-    par_cha[1] = fClengthM1[iplan-1]/2.;
-    par_cha[2] = kCcframe/2.;
-    xpos       = 0.;
-    ypos       = fClengthI[iplan-1]/2. + fClengthM1[iplan-1]/2.;
-    zpos       = kCcframe/2.           - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UCFM",iplan         ,"TRD1",xpos, ypos,zpos,0,"MANY",par_cha,npar_cha);
-    gMC->Gsposp("UCFM",iplan+  kNplan,"TRD1",xpos,-ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-    // the inner part of the carbon frame
-    par_cha[0] = fCwidth[iplan-1]/2.    - kCcthick;
-    par_cha[1] = fClengthM1[iplan-1]/2. - kCcthick;
-    par_cha[2] = kCcframe/2.;
-    xpos       = 0.;
-    ypos       = fClengthI[iplan-1]/2. + fClengthM1[iplan-1]/2.;
-    zpos       = kCcframe/2.           - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UCIM",iplan         ,"TRD1",xpos, ypos,zpos,0,"ONLY",par_cha,npar_cha);
-    gMC->Gsposp("UCIM",iplan+  kNplan,"TRD1",xpos,-ypos,zpos,0,"ONLY",par_cha,npar_cha);
-
-    // Only for the geometry with holes
-    if (fHole) {
-
-      // the aluminum frame
-      par_cha[0] = fCwidth[iplan-1]/2.;
-      par_cha[1] = fClengthM2[iplan-1]/2.;
-      par_cha[2] = kCaframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthM2[iplan-1]/2. - kSlenTR2/2.;
-      zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UAFM",iplan+2*kNplan,"TRD2",xpos, ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-      // the inner part of the aluminum frame
-      par_cha[0] = fCwidth[iplan-1]/2.    - kCathick;
-      par_cha[1] = fClengthM2[iplan-1]/2. - kCathick;
-      par_cha[2] = kCaframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthM2[iplan-1]/2. - kSlenTR2/2.;
-      zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UAIM",iplan+2*kNplan,"TRD2",xpos, ypos,zpos,0,"ONLY",par_cha,npar_cha);
-
-      // the carbon frame
-      par_cha[0] = fCwidth[iplan-1]/2.;
-      par_cha[1] = fClengthM2[iplan-1]/2.;
-      par_cha[2] = kCcframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthM2[iplan-1]/2. - kSlenTR2/2.;
-      zpos       = kCcframe/2.            - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UCFM",iplan+2*kNplan,"TRD2",xpos, ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-      // the inner part of the carbon frame
-      par_cha[0] = fCwidth[iplan-1]/2.    - kCcthick;
-      par_cha[1] = fClengthM2[iplan-1]/2. - kCcthick;
-      par_cha[2] = kCcframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthM2[iplan-1]/2. - kSlenTR2/2.;
-      zpos       = kCcframe/2.            - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UCIM",iplan+2*kNplan,"TRD2",xpos, ypos,zpos,0,"ONLY",par_cha,npar_cha);
-      
-    }
+  AliTRDrawData rawWriter;
+  if (!rawWriter.Digits2Raw(digits)) {
+    AliError("The raw writer could not load the digits tree");
+  }
 
-    // The outer chambers ---------------------------------------------------------------
-
-    // the aluminum frame
-    par_cha[0] = fCwidth[iplan-1]/2.;
-    par_cha[1] = fClengthO1[iplan-1]/2.;
-    par_cha[2] = kCaframe/2.;
-    xpos       = 0.;
-    ypos       = fClengthI[iplan-1]/2. + fClengthM1[iplan-1]    + fClengthO1[iplan-1]/2.;
-    zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UAFO",iplan         ,"TRD1",xpos, ypos,zpos,0,"MANY",par_cha,npar_cha);
-    gMC->Gsposp("UAFO",iplan+  kNplan,"TRD1",xpos,-ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-    // the inner part of the aluminum frame
-    par_cha[0] = fCwidth[iplan-1]/2.    - kCathick;
-    par_cha[1] = fClengthO1[iplan-1]/2. - kCathick;
-    par_cha[2] = kCaframe/2.;
-    xpos       = 0.;
-    ypos       = fClengthI[iplan-1]/2. + fClengthM1[iplan-1]    + fClengthO1[iplan-1]/2.;
-    zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UAIO",iplan         ,"TRD1",xpos, ypos,zpos,0,"ONLY",par_cha,npar_cha);
-    gMC->Gsposp("UAIO",iplan+  kNplan,"TRD1",xpos,-ypos,zpos,0,"ONLY",par_cha,npar_cha);
-
-    // the carbon frame
-    par_cha[0] = fCwidth[iplan-1]/2.;
-    par_cha[1] = fClengthO1[iplan-1]/2.;
-    par_cha[2] = kCcframe/2.;
-    xpos       = 0.;
-    ypos       = fClengthI[iplan-1]/2. + fClengthM1[iplan-1]    + fClengthO1[iplan-1]/2.;
-    zpos       = kCcframe/2.           - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UCFO",iplan,         "TRD1",xpos, ypos,zpos,0,"MANY",par_cha,npar_cha);
-    gMC->Gsposp("UCFO",iplan+  kNplan,"TRD1",xpos,-ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-    // the inner part of the carbon frame
-    par_cha[0] = fCwidth[iplan-1]/2.    - kCcthick;
-    par_cha[1] = fClengthO1[iplan-1]/2. - kCcthick;
-    par_cha[2] = kCcframe/2.;
-    xpos       = 0.;
-    ypos       = fClengthI[iplan-1]/2. + fClengthM1[iplan-1]    + fClengthO1[iplan-1]/2.;
-    zpos       = kCcframe/2.           - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-    gMC->Gsposp("UCIO",iplan         ,"TRD1",xpos, ypos,zpos,0,"ONLY",par_cha,npar_cha);
-    gMC->Gsposp("UCIO",iplan+  kNplan,"TRD1",xpos,-ypos,zpos,0,"ONLY",par_cha,npar_cha);
-
-    // Only for the geometry with holes
-    if (fHole) {
-
-      // the aluminum frame
-      par_cha[0] = fCwidth[iplan-1]/2.;
-      par_cha[1] = fClengthO2[iplan-1]/2.;
-      par_cha[2] = kCaframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthM2[iplan-1]    + fClengthO2[iplan-1]/2. - kSlenTR2/2.;
-      zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UAFO",iplan+2*kNplan,"TRD2",xpos, ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-      // the inner part of the aluminum frame
-      par_cha[0] = fCwidth[iplan-1]/2.    - kCathick;
-      par_cha[1] = fClengthO2[iplan-1]/2. - kCathick;
-      par_cha[2] = kCaframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthM2[iplan-1]    + fClengthO2[iplan-1]/2. - kSlenTR2/2.;
-      zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UAIO",iplan+2*kNplan,"TRD2",xpos, ypos,zpos,0,"ONLY",par_cha,npar_cha);
-
-      // the carbon frame
-      par_cha[0] = fCwidth[iplan-1]/2.;
-      par_cha[1] = fClengthO2[iplan-1]/2.;
-      par_cha[2] = kCcframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthM2[iplan-1]    + fClengthO2[iplan-1]/2. - kSlenTR2/2.;
-      zpos       = kCcframe/2.            - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UCFO",iplan+2*kNplan,"TRD2",xpos, ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-      // the inner part of the carbon frame
-      par_cha[0] = fCwidth[iplan-1]/2.    - kCcthick;
-      par_cha[1] = fClengthO2[iplan-1]/2. - kCcthick;
-      par_cha[2] = kCcframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthM2[iplan-1]    + fClengthO2[iplan-1]/2. - kSlenTR2/2.;
-      zpos       = kCcframe/2.            - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UCIO",iplan+2*kNplan,"TRD2",xpos, ypos,zpos,0,"ONLY",par_cha,npar_cha);
-
-      // the aluminum frame
-      par_cha[0] = fCwidth[iplan-1]/2.;
-      par_cha[1] = fClengthO3[iplan-1]/2.;
-      par_cha[2] = kCaframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthO3[iplan-1]/2. - kSlenTR3/2.;
-      zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UAFO",iplan+4*kNplan,"TRD3",xpos, ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-      // the inner part of the aluminum frame
-      par_cha[0] = fCwidth[iplan-1]/2.    - kCathick;
-      par_cha[1] = fClengthO3[iplan-1]/2. - kCathick;
-      par_cha[2] = kCaframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthO3[iplan-1]/2. - kSlenTR3/2.;
-      zpos       = kCheight - kCaframe/2. - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UAIO",iplan+4*kNplan,"TRD3",xpos, ypos,zpos,0,"ONLY",par_cha,npar_cha);
-
-      // the carbon frame
-      par_cha[0] = fCwidth[iplan-1]/2.;
-      par_cha[1] = fClengthO3[iplan-1]/2.;
-      par_cha[2] = kCcframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthO3[iplan-1]/2. - kSlenTR3/2.;
-      zpos       = kCcframe/2.            - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UCFO",iplan+4*kNplan,"TRD3",xpos, ypos,zpos,0,"MANY",par_cha,npar_cha);
-
-      // the inner part of the carbon frame
-      par_cha[0] = fCwidth[iplan-1]/2.    - kCcthick;
-      par_cha[1] = fClengthO3[iplan-1]/2. - kCcthick;
-      par_cha[2] = kCcframe/2.;
-      xpos       = 0.;
-      ypos       = fClengthO3[iplan-1]/2. - kSlenTR3/2.;
-      zpos       = kCcframe/2.            - kSheight/2. + (iplan-1) * (kCheight + kCspace);
-      gMC->Gsposp("UCIO",iplan+4*kNplan,"TRD3",xpos, ypos,zpos,0,"ONLY",par_cha,npar_cha);
+  fLoader->UnloadDigits();
 
-    }
+}
 
-  }
+//_____________________________________________________________________________
+void AliTRD::AddHit(Int_t track, Int_t det, Float_t *hits, Int_t q
+                  , Float_t time, Bool_t inDrift)
+{
+  //
+  // Add a hit for the TRD
+  // 
 
-  if (fHole) {
-    xpos     = 0.;
-    ypos     = 0.;
-    zpos     = 0.;
-    gMC->Gspos("TRD1",1,"BTR1",xpos,ypos,zpos,0,"ONLY");
-    gMC->Gspos("TRD2",1,"BTR2",xpos,ypos,zpos,0,"ONLY");
-    gMC->Gspos("TRD3",1,"BTR3",xpos,ypos,zpos,0,"ONLY");
+  TClonesArray &lhits = *fHits;
+  AliTRDhit *hit = new(lhits[fNhits++]) AliTRDhit(fIshunt
+                                                 ,track
+                                                 ,det
+                                                 ,hits
+                                                 ,q
+                                                 ,time);
+
+  if (inDrift) {
+    hit->SetDrift();
   }
   else {
-    xpos     = 0.;
-    ypos     = 0.;
-    zpos     = 0.;
-    gMC->Gspos("TRD1",1,"BTR1",xpos,ypos,zpos,0,"ONLY");
-    gMC->Gspos("TRD1",2,"BTR2",xpos,ypos,zpos,0,"ONLY");
-    gMC->Gspos("TRD1",3,"BTR3",xpos,ypos,zpos,0,"ONLY");
+    hit->SetAmplification();
+  }
+
+  if (q < 0) {
+    hit->SetTRphoton();
   }
 
 }
  
 //_____________________________________________________________________________
+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) {
+    AliFatal("The TRD needs the FRAME to be defined first");
+  }
+
+  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();
+  Int_t   isxfld = ((AliMagF*)TGeoGlobalMagField::Instance()->GetField())->Integ();
+  Float_t sxmgmx = ((AliMagF*)TGeoGlobalMagField::Instance()->GetField())->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;
+  Float_t ape[2]    = { 12.011 ,  1.0079 };
+  Float_t zpe[2]    = {  6.0   ,  1.0    };
+  Float_t wpe[2]    = {  1.0   ,  2.0    };
+  Float_t dpe       = 0.95;
 
   // 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;
+  Float_t aco[2]    = { 12.011 , 15.9994 };
+  Float_t zco[2]    = {  6.0   ,  8.0    };
+  Float_t wco[2]    = {  1.0   ,  2.0    };
+  Float_t dco       = 0.00186; // at 20C
 
   // 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;
+  Float_t awa[2]    = {  1.0079, 15.9994 };
+  Float_t zwa[2]    = {  1.0   ,  8.0    };
+  Float_t wwa[2]    = {  2.0   ,  1.0    };
+  Float_t dwa       = 1.0;
+
+  // For plexiglas (C5H8O2)
+  Float_t apg[3]    = { 12.011 ,  1.0079, 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,  1.0079, 12.011  }; 
+  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 Araldite, low density epoxy (C18H19O3)
+  Float_t aAral[3]  = { 15.9994,  1.0079, 12.011  }; 
+  Float_t zAral[3]  = {  8.0   ,  1.0   ,  6.0    }; 
+  Float_t wAral[3]  = {  3.0   , 19.0   , 18.0    }; 
+  Float_t dAral     = 1.05; 
+
+  // For air  
+  Float_t aAir[4]   = { 12.011   , 14.0     , 15.9994  , 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-03;
+
+  // For G10
+  Float_t aG10[4]   = {  1.0079  , 12.011   , 15.9994  , 28.086    };
+  Float_t zG10[4]   = {  1.0     ,  6.0     ,  8.0     , 14.0      };
+  Float_t wG10[4]   = {  0.15201 ,  0.10641 ,  0.49444 ,  0.24714  };
+  Float_t dG10      = 1.7;
 
   // For Xe/CO2-gas-mixture 
-  // Xe-content of the Xe/CO2-mixture (90% / 10%) 
-  Float_t fxc    = .90;
-  // Xe-content of the Xe/Isobutane-mixture (97% / 3%) 
-  Float_t fxi    = .97;
-  Float_t dxe    = .005858;
+  Float_t aXeCO2[3] = { 131.29   ,  12.0107 ,  15.9994  };
+  Float_t zXeCO2[3] = {  54.0    ,   6.0    ,   8.0     };
+  Float_t wXeCO2[3] = {   8.5    ,   1.5    ,   3.0     }; 
+  // Xe-content of the Xe/CO2-mixture (85% / 15%) 
+  Float_t fxc       = 0.85;
+  Float_t dxe       = 0.00549; // at 20C
+  Float_t dgmXe     = fxc * dxe + (1.0 - fxc) * dco;
+
+  // For Ar/CO2-gas-mixture
+  Float_t aArCO2[3] = {  39.948  ,  12.0107 ,  15.9994  };
+  Float_t zArCO2[3] = {  18.0    ,   6.0    ,   8.0     };
+  Float_t wArCO2[3] = {   8.2    ,   1.8    ,   3.6     }; 
+  // Ar-content of the Ar/CO2-mixture (82% / 18%) 
+  Float_t fac       = 0.82;
+  Float_t dar       = 0.00166; // at 20C
+  Float_t dgmAr     = fac * dar + (1.0 - fac) * dco;
   
   // 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], dgm, zgm[2], wgm[2];
-  Int_t   nbuf;
+  Float_t tmaxfd    = -10.0;
+  Float_t stemax    = -1.0e10;
+  Float_t deemax    = -0.1;
+  Float_t epsil     =  1.0e-4;
+  Float_t stmin     = -0.001;
   
   //////////////////////////////////////////////////////////////////////////
   //     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( 1, "Al"   ,  26.98, 13.0, 2.7     ,     8.9 ,    37.2);
+  AliMaterial( 4, "Xe"   , 131.29, 54.0, dxe     ,  1546.16,     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(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(18, "Fe"   ,  55.85, 26.0, 7.87    ,     1.76,    14.8);
 
   // Mixtures 
-  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(13,"Water$",          awa, zwa, dwa, -2, wwa);
-
-  // Gas mixtures
-  Char_t namate[21];
-  // Xe/CO2-mixture
-  // Get properties of Xe 
-  gMC->Gfmate((*fIdmate)[4], namate, agm[0], zgm[0], d, radl, absl, buf, nbuf);
-  // Get properties of CO2 
-  gMC->Gfmate((*fIdmate)[8], namate, agm[1], zgm[1], d, radl, absl, buf, nbuf);
-  // Create gas mixture 
-  wgm[0] = fxc;
-  wgm[1] = 1. - fxc;
-  dgm    = wgm[0] * dxe + wgm[1] * dco;
-  AliMixture(10, "Gas mixture 1$", agm, zgm, dgm,  2, wgm);
-  // 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;
-  dgm    = wgm[0] * dxe + wgm[1] * dis;
-  AliMixture(11, "Gas mixture 2$", agm, zgm, dgm,  2, wgm);
+  AliMixture(2, "Air"         , aAir,   zAir,   dAir,    4, wAir  );
+  AliMixture(3, "Polyethilene", ape,    zpe,    dpe,    -2, wpe   );
+  AliMixture(8, "CO2",          aco,    zco,    dco,    -2, wco   );
+  if      (AliTRDSimParam::Instance()->IsXenon()) {
+    AliMixture(10,"XeCO2",        aXeCO2, zXeCO2, dgmXe,  -3, wXeCO2);
+  }
+  else if (AliTRDSimParam::Instance()->IsArgon()) {
+    AliInfo("Gas mixture: Ar C02 (80/20)");
+    AliMixture(10,"ArCO2",        aArCO2, zArCO2, dgmAr,  -3, wArCO2);
+  }
+  else {
+    AliFatal("Wrong gas mixture");
+    exit(1);
+  }
+  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);
+  AliMixture(19,"Araldite",     aAral,  zAral,  dAral,  -3, wAral );
+
   //////////////////////////////////////////////////////////////////////////
   //     Tracking Media Parameters 
   //////////////////////////////////////////////////////////////////////////
 
   // Al Frame 
-  AliMedium(1, "Al Frame$",   1, 0, ISXFLD, SXMGMX
-                , tmaxfd, stemax, deemax, epsil, stmin);
+  AliMedium( 1,"Al Frame"   , 1,0,isxfld,sxmgmx
+              ,tmaxfd,stemax,deemax,epsil,stmin);
   // Air 
-  AliMedium(2, "Air$",        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);
+  AliMedium( 2,"Air"        , 2,0,isxfld,sxmgmx
+              ,tmaxfd,stemax,deemax,epsil,stmin);
+  // Wires
+  AliMedium( 3,"Wires"      , 5,0,isxfld,sxmgmx
+              ,tmaxfd,stemax,deemax,epsil,stmin);
+  // All other ROB materials (caps, etc.)
+  AliMedium( 4,"ROB Other"  , 5,0,isxfld,sxmgmx
+              ,tmaxfd,stemax,deemax,epsil,stmin);
   // Cu pads 
-  AliMedium(5, "Padplane$",   5, 1, ISXFLD, SXMGMX
-                , tmaxfd, stemax, deemax, epsil, stmin);
+  AliMedium( 5,"Padplane"   , 5,1,isxfld,sxmgmx
+              ,tmaxfd,stemax,deemax,epsil,stmin);
   // Fee + cables 
-  AliMedium(6, "Readout$",    1, 0, ISXFLD, SXMGMX
-                , tmaxfd, stemax, deemax, epsil, stmin);
+  AliMedium( 6,"Readout"    , 5,0,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$",        8, 0, ISXFLD, SXMGMX
-                , tmaxfd, stemax, deemax, epsil, stmin);
+  AliMedium( 7,"C Frame"    , 6,0,isxfld,sxmgmx
+              ,tmaxfd,stemax,deemax,epsil,stmin);
+  // INOX of cooling bus bars
+  AliMedium( 8,"Cooling bus",18,0,isxfld,sxmgmx
+              ,tmaxfd,stemax,deemax,epsil,stmin);
+  // Gas-mixture (Xe/CO2) 
+  AliMedium( 9,"Gas-mix"    ,10,1,isxfld,sxmgmx
+              ,tmaxfd,stemax,deemax,epsil,stmin);
+  // Nomex-honeycomb
+  AliMedium(10,"Nomex"      ,12,0,isxfld,sxmgmx
+              ,tmaxfd,stemax,deemax,epsil,stmin);
+  // Araldite glue
+  AliMedium(11,"Glue"       ,19,0,isxfld,sxmgmx
+              ,tmaxfd,stemax,deemax,epsil,stmin);
   // G10-plates
-  AliMedium(13, "G10-plates$",12, 0, ISXFLD, SXMGMX
-                , tmaxfd, stemax, deemax, epsil, stmin);
+  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);
-
-}
-
-//_____________________________________________________________________________
-void AliTRD::DrawModule()
-{
-  //
-  // 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 (fHole) {
-    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("TRD1","SEEN", 0);
-    gMC->Gsatt("TRD2","SEEN", 0);
-    gMC->Gsatt("TRD3","SEEN", 0);
+  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
+  Float_t dmy  = 1.39;
+  fFoilDensity = dmy;
+  if      (AliTRDSimParam::Instance()->IsXenon()) {
+    fGasDensity       = dgmXe;
+    fGasNobleFraction = fxc;
   }
-  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("TRD1","SEEN", 0);
+  else if (AliTRDSimParam::Instance()->IsArgon()) {
+    fGasDensity       = dgmAr;
+    fGasNobleFraction = fac;
   }
-  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;
 
 }
  
@@ -994,133 +517,35 @@ Int_t AliTRD::DistancetoPrimitive(Int_t , Int_t )
 void AliTRD::Init()
 {
   //
-  // Initialise the TRD detector after the geometry has been created
+  // Initialize the TRD detector after the geometry has been created
   //
 
-  Int_t i;
-  Int_t iplan;
-  
-  printf("\n");
-  for(i=0;i<35;i++) printf("*");
-  printf(" TRD_INIT ");
-  for(i=0;i<35;i++) printf("*");
-  printf("\n");
-  
-  // Here the TRD initialisation code (if any!)
-  if (fGasMix == 1) 
-    printf("          Gas Mixture: 90%% Xe + 10%% CO2\n");
-  else
-    printf("          Gas Mixture: 97%% Xe + 3%% Isobutane\n");
-
-  if (fHole)
-    printf("          Geometry with holes\n");
-  else
-    printf("          Full geometry\n");
-
-  // The default pad dimensions
-  if (!(fRowPadSize))  fRowPadSize  = 4.5;
-  if (!(fColPadSize))  fColPadSize  = 1.0;
-  if (!(fTimeBinSize)) fTimeBinSize = 0.1;
-
-  // The maximum number of pads
-  // and the position of pad 0,0,0 
-  // 
-  // chambers seen from the top:
-  //     +----------------------------+
-  //     |                            |
-  //     |                            |     ^
-  //     |                            | rphi|
-  //     |                            |     |
-  //     |0                           |     | 
-  //     +----------------------------+     +------>
-  //                                             z 
-  // chambers seen from the side:           ^
-  //     +----------------------------+ time|
-  //     |                            |     |
-  //     |0                           |     |
-  //     +----------------------------+     +------>
-  //                                             z
-  //                                             
-  for (iplan = 0; iplan < kNplan; iplan++) {
-
-    // The pad row (z-direction)
-    for (Int_t isect = 0; isect < kNsect; isect++) {
-      Float_t clengthI = fClengthI[iplan];
-      Float_t clengthM = fClengthM1[iplan];
-      Float_t clengthO = fClengthO1[iplan];
-      if (fHole) {
-        switch (isect) {
-        case 12:
-       case 13:
-       case 14:
-       case 15:
-       case 16:
-          clengthM = fClengthM2[iplan];
-          clengthO = fClengthO2[iplan];
-          break;
-        case 4:
-       case 5:
-       case 6:
-          clengthO = fClengthO3[iplan];
-          break;
-        };
-      }
-      fRowMax[iplan][0][isect] = 1 + TMath::Nint((clengthO - 2. * kCcthick) 
-                                                           / fRowPadSize - 0.5);
-      fRowMax[iplan][1][isect] = 1 + TMath::Nint((clengthM - 2. * kCcthick) 
-                                                           / fRowPadSize - 0.5);
-      fRowMax[iplan][2][isect] = 1 + TMath::Nint((clengthI - 2. * kCcthick) 
-                                                           / fRowPadSize - 0.5);
-      fRowMax[iplan][3][isect] = 1 + TMath::Nint((clengthM - 2. * kCcthick) 
-                                                           / fRowPadSize - 0.5);
-      fRowMax[iplan][4][isect] = 1 + TMath::Nint((clengthO - 2. * kCcthick) 
-                                                           / fRowPadSize - 0.5);
-      fRow0[iplan][0][isect]   = -clengthI/2. - clengthM - clengthO + kCcthick; 
-      fRow0[iplan][1][isect]   = -clengthI/2. - clengthM            + kCcthick;
-      fRow0[iplan][2][isect]   = -clengthI/2.                       + kCcthick;
-      fRow0[iplan][3][isect]   =  clengthI/2.                       + kCcthick; 
-      fRow0[iplan][4][isect]   =  clengthI/2. + clengthM            + kCcthick; 
-    }
-
-    // The pad column (rphi-direction)  
-    fColMax[iplan]    = 1 + TMath::Nint((fCwidth[iplan] - 2. * kCcthick) 
-                                                        / fColPadSize - 0.5);
-    fCol0[iplan]      = -fCwidth[iplan]/2. + kCcthick;
+  AliDebug(1,"++++++++++++++++++++++++++++++++++++++++++++++");
 
+  if (fGeometry->IsVersion() != 1) {
+    AliError("Not a valid geometry");
   }
 
-  // The time bucket
-  fTimeMax = 1 + TMath::Nint(kDrThick / fTimeBinSize - 0.5);
-  for (iplan = 0; iplan < kNplan; iplan++) {
-    fTime0[iplan]   = kRmin + kCcframe/2. + kDrZpos - 0.5 * kDrThick
-                            + iplan * (kCheight + kCspace);
-  } 
+  // Special tracking options for charged particles for XeCO2
+  gMC->Gstpar((* fIdtmed)[9],"DRAY"    , 1.0);
+  gMC->Gstpar((* fIdtmed)[9],"STRA"    , 1.0); 
+  gMC->Gstpar((* fIdtmed)[9],"LOSS"    ,13.0);      // Specific energy loss
+  gMC->Gstpar((* fIdtmed)[9],"PRIMIO_E",23.53);     // 1st ionisation potential
+  gMC->Gstpar((* fIdtmed)[9],"PRIMIO_N",19.344431); // Number of primaries
 
 }
 
 //_____________________________________________________________________________
-void AliTRD::MakeBranch(Option_t* option)
+void AliTRD::ResetDigits()
 {
   //
-  // Create Tree branches for the TRD digits and cluster.
+  // Reset number of digits and the digits array for this detector
   //
 
-  Int_t  buffersize = 4000;
-  Char_t branchname[15];
-
-  AliDetector::MakeBranch(option);
+  fNdigits = 0;
 
-  Char_t *D = strstr(option,"D");
-  sprintf(branchname,"%s",GetName());
-  if (fDigits   && gAlice->TreeD() && D) {
-    gAlice->TreeD()->Branch(branchname,&fDigits,  buffersize);
-    printf("* AliTRD::MakeBranch * Making Branch %s for digits in TreeD\n",branchname);
-  }
-
-  sprintf(branchname,"%scluster",GetName());
-  if (fClusters && gAlice->TreeD() && D) {
-    gAlice->TreeD()->Branch(branchname,&fClusters,buffersize);
-    printf("* AliTRD::MakeBranch * Making Branch %s for cluster in TreeD\n",branchname);
+  if (fDigits) {
+    fDigits->Clear();
   }
 
 }
@@ -1132,170 +557,71 @@ void AliTRD::SetTreeAddress()
   // Set the branch addresses for the trees.
   //
 
-  Char_t branchname[15];
-
-  AliDetector::SetTreeAddress();
-
-  TBranch *branch;
-  TTree   *treeD = gAlice->TreeD();
-
-  if (treeD) {
-    sprintf(branchname,"%scluster",GetName());    
-    if (fClusters) {
-      branch = treeD->GetBranch(branchname);
-      if (branch) branch->SetAddress(&fClusters);
-    }
+  if (fLoader->TreeH() && 
+      (fHits == 0x0)) {
+    fHits = new TClonesArray("AliTRDhit",405);
   }
+  AliDetector::SetTreeAddress();
 
 }
 
 //_____________________________________________________________________________
-void AliTRD::SetGasMix(Int_t imix)
+Bool_t AliTRD::Raw2SDigits(AliRawReader *rawReader)
 {
   //
-  // Defines the gas mixture (imix=0:  Xe/Isobutane imix=1: Xe/CO2)
+  // Converts RAW data to SDigits
   //
-  
-  if ((imix < 0) || (imix > 1)) {
-    printf("Wrong input value: %d\n",imix);
-    printf("Use standard setting\n");
-    fGasMix = 0;
-    return;
-  }
-
-  fGasMix = imix;
-
-}
-
-//______________________________________________________________________________
-void AliTRD::Streamer(TBuffer &R__b)
-{
-   // Stream an object of class AliTRD.
-
-   if (R__b.IsReading()) {
-      Version_t R__v = R__b.ReadVersion(); if (R__v) { }
-      AliDetector::Streamer(R__b);
-      R__b >> fGasMix;
-      R__b.ReadStaticArray(fClengthI);
-      R__b.ReadStaticArray(fClengthM1);
-      R__b.ReadStaticArray(fClengthM2);
-      R__b.ReadStaticArray(fClengthO1);
-      R__b.ReadStaticArray(fClengthO2);
-      R__b.ReadStaticArray(fClengthO3);
-      R__b.ReadStaticArray(fCwidth);
-      R__b.ReadStaticArray((int*)fRowMax);
-      R__b.ReadStaticArray(fColMax);
-      R__b >> fTimeMax;
-      R__b.ReadStaticArray((float*)fRow0);
-      R__b.ReadStaticArray(fCol0);
-      R__b.ReadStaticArray(fTime0);
-      R__b >> fRowPadSize;
-      R__b >> fColPadSize;
-      R__b >> fTimeBinSize;
-      R__b >> fHole;
-      // Stream the pointers but not the TClonesArray
-      R__b >> fClusters;     // diff
-      //R__b >> fNclusters;
-   } else {
-      R__b.WriteVersion(AliTRD::IsA());
-      AliDetector::Streamer(R__b);
-      R__b << fGasMix;
-      R__b.WriteArray(fClengthI, 6);
-      R__b.WriteArray(fClengthM1, 6);
-      R__b.WriteArray(fClengthM2, 6);
-      R__b.WriteArray(fClengthO1, 6);
-      R__b.WriteArray(fClengthO2, 6);
-      R__b.WriteArray(fClengthO3, 6);
-      R__b.WriteArray(fCwidth, 6);
-      R__b.WriteArray((int*)fRowMax, 540);
-      R__b.WriteArray(fColMax, 6);
-      R__b << fTimeMax;
-      R__b.WriteArray((float*)fRow0, 540);
-      R__b.WriteArray(fCol0, 6);
-      R__b.WriteArray(fTime0, 6);
-      R__b << fRowPadSize;
-      R__b << fColPadSize;
-      R__b << fTimeBinSize;
-      R__b << fHole;
-      // Stream the pointers but not the TClonesArrays
-      R__b << fClusters;     // diff
-      //R__b << fNclusters;
-   }
-
-}
 
-ClassImp(AliTRDhit)
-//_____________________________________________________________________________
-AliTRDhit::AliTRDhit(Int_t shunt, Int_t track, Int_t *vol, Float_t *hits)
-          :AliHit(shunt, track)
-{
-  //
-  // Create a TRD hit
-  //
+  AliLoader *loader = fRunLoader->GetLoader("TRDLoader");
+  if (!loader) {
+    AliError("Can not get TRD loader from Run Loader");
+    return kFALSE;
+  }
+    
+  TTree *tree = 0;
+  tree = loader->TreeS();
+  if (!tree) {
+    loader->MakeTree("S");
+    tree = loader->TreeS();
+  }
 
-  // Store volume hierarchy
-  fSector  = vol[0]; 
-  fChamber = vol[1];
-  fPlane   = vol[2];
-  
-  // Store position and charge
-  fX       = hits[0];
-  fY       = hits[1];
-  fZ       = hits[2];
-  fQ       = hits[3];
+  AliTRDrawData       *rawdata        = new AliTRDrawData();
+  AliTRDdigitsManager *sdigitsManager = rawdata->Raw2Digits(rawReader);
+  if (sdigitsManager) {
+    sdigitsManager->SetSDigits(kTRUE);
+    sdigitsManager->MakeBranch(tree);
+    sdigitsManager->WriteDigits();
+    return kTRUE;
+  } 
+  else {
+    return kFALSE;
+  }
 
 }
 
-ClassImp(AliTRDdigit)
-
 //_____________________________________________________________________________
-AliTRDdigit::AliTRDdigit(Int_t *tracks, Int_t *digits)
-            :AliDigit(tracks)
+AliLoader* AliTRD::MakeLoader(const char* topfoldername)
 {
-  //
-  // Create a TRD digit
-  //
-
-  // Store the volume hierarchy
-  fSector  = digits[0];
-  fChamber = digits[1];
-  fPlane   = digits[2];
-
-  // Store the row, pad, and time bucket number
-  fRow     = digits[3];
-  fCol     = digits[4];
-  fTime    = digits[5];
+ fLoader = new AliLoader(GetName(),topfoldername);
 
-  // Store the signal amplitude
-  fSignal  = digits[6];
+ AliInfo("Adding Tracklets-loader");
+ AliDataLoader *dl = new AliDataLoader("TRD.Tracklets.root","tracklets", "tracklets");
+ fLoader->AddDataLoader(dl);
 
+ return fLoader;
 }
 
-ClassImp(AliTRDcluster)
-
 //_____________________________________________________________________________
-AliTRDcluster::AliTRDcluster(Int_t *tracks, Int_t *cluster, Float_t* position)
-              :TObject()
+AliTRD &AliTRD::operator=(const AliTRD &trd)
 {
   //
-  // Create a TRD cluster
+  // Assignment operator
   //
 
-  fSector    = cluster[0];
-  fChamber   = cluster[1];
-  fPlane     = cluster[2];
-
-  fTimeSlice = cluster[3];
-  fEnergy    = cluster[4];
-
-  fX         = position[0];
-  fY         = position[1];
-  fZ         = position[2];
+  if (this != &trd) {
+    ((AliTRD &) trd).Copy(*this);
+  }
 
-  fTracks[0] = tracks[0];
-  fTracks[1] = tracks[1];
-  fTracks[2] = tracks[2];
+  return *this;
 
 }
-