ITS/AliITSv11GeometrySDD.cxx

   1 /**************************************************************************
   2  * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
   3  *                                                                        *
   4  * Author: The ALICE Off-line Project.                                    *
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  15
  16 //*************************************************************************
  17 // SDD geometry, based on ROOT geometrical modeler
  18 //
  19 // Ludovic Gaudichet (Ludovic.Gaudichet@to.infn.it)
  20 //*************************************************************************
  21
  22
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25
  26 // General Root includes
  27 #include <Riostream.h>
  28 #include <TMath.h>
  29
  30 // Root Geometry includes
  31 #include <TGeoManager.h>
  32 #include <TGeoVolume.h>
  33 #include <TGeoPcon.h>
  34 #include <TGeoCone.h>
  35 #include <TGeoTube.h>
  36 #include <TGeoArb8.h>
  37 #include <TGeoCompositeShape.h>
  38 #include <TGeoMatrix.h>
  39 #include <TGeoMaterial.h>
  40 #include <TGeoMedium.h>
  41
  42 #include "AliITSv11Geometry.h"
  43 #include "AliITSv11GeometrySDD.h"
  44
  45
  46
  47 ClassImp(AliITSv11GeometrySDD)
  48
  49
  50 AliITSv11GeometrySDD::AliITSv11GeometrySDD():AliITSv11Geometry() {
  51   fAddOnlyLadder3 = -1;
  52   fAddOnlyLadder4 = -1;
  53   fAddOnlySegment = 0;
  54   SetGeomParameters();
  55 };
  56 //----------------------------------------------------------------------
  57 AliITSv11GeometrySDD::AliITSv11GeometrySDD(Int_t debug):AliITSv11Geometry(debug) {
  58   fAddOnlyLadder3 = -1;
  59   fAddOnlyLadder4 = -1;
  60   fAddOnlySegment = 0;
  61   SetGeomParameters();
  62 };
  63 //----------------------------------------------------------------------
  64 void AliITSv11GeometrySDD::SetGeomParameters() {
  65
  66   fSegmentLength       = 37.2*2*fgkmm;
  67   fLadderWidth         = 50.0*fgkmm;
  68   fLadderHeight        = 30.0*fgkmm;
  69   fLadderBeamRadius    =  0.6*fgkmm;
  70   fLadderLa            =  3.*fgkmm;
  71   fLadderHa            =  0.6*fgkmm; //total pifometer
  72   fLadderLb            =  3.7*fgkmm;
  73   fLadderHb            =  0.6*fgkmm; //total pifometer
  74   fLadderl             =  0.25*fgkmm;
  75
  76   fBottomBeamAngle     = 56.5;
  77   fBeamSidePhi         = 65;
  78
  79   fWaferThickness      = 0.3*fgkmm;
  80   fWaferWidth          = 72.5*fgkmm;
  81   fWaferLength         = 87.6*fgkmm;
  82
  83   fHybridLength        = (37.2*2-15)*fgkmm; //total pifometer
  84   fHybridWidth         = 35*fgkmm; //total pifometer
  85
  86   fLadWaferSep         = 2*fgkmm;
  87   fPinSuppWidth        = 2.5*fgkmm; // pifometer
  88   fPinSuppHeight       = 2.*fgkmm; // pifometer
  89   fPinSuppRmax         = 2.5/2.*fgkmm;
  90   fPinR                = 1.5/2.*fgkmm;
  91   fPinSuppLength       = 5.*fgkmm;
  92   fPinSuppThickness    = 0.5*fgkmm;
  93   fPinSuppConeAngle    = 4;
  94
  95   fLay3Rmin            = 130.*fgkmm; //not min! Rmin virtual tube
  96   fLay3Rmax            = 190.*fgkmm; //not min! Rmax virtual tube
  97   fLay3Length          = (524.+0.)*fgkmm; // ladder+supporting rings (length of the virtual tube)
  98   fLay3LadderLength    = 524.*fgkmm;
  99   fLay3DetShortRadius  = 146.0*fgkmm;
 100   fLay3DetLongRadius   = 152.0*fgkmm;
 101   fLay3LaddShortRadius = fLay3DetShortRadius-fLadderBeamRadius+(8-1)*fgkmm; // radius from the center to the CF ladder
 102   fLay3LaddLongRadius  = fLay3DetLongRadius-fLadderBeamRadius+(8-1)*fgkmm; // radius from the center to the CF ladder
 103   fLay3LaddTopCornerEnd = 15.6*fgkmm;
 104   fLay3Ndet            = 6;
 105   fLay3Nladd           = 14;
 106
 107   fLay4Rmin            = 220.*fgkmm; //not min! Rmin virtual tube
 108   fLay4Rmax            = 290.*fgkmm; //not min! Rmax virtual tube
 109   fLay4Length          = (671.+0.)*fgkmm; // ladder+supporting rings (length of the virtual tube)
 110   fLay4LadderLength    = 671.*fgkmm;
 111   fLay4DetShortRadius  = 235.0*fgkmm;
 112   fLay4DetLongRadius   = 240.5*fgkmm;
 113   fLay4LaddShortRadius = fLay4DetShortRadius-fLadderBeamRadius+(8-1)*fgkmm; // radius from the center to the CF ladder
 114   fLay4LaddLongRadius  = fLay4DetLongRadius-fLadderBeamRadius+(8-1)*fgkmm;  // radius from the center to the CF ladder
 115   fLay4LaddTopCornerEnd = 15.6*fgkmm;
 116   fLay4Ndet            = 8;
 117   fLay4Nladd           = 22;
 118
 119   for (Int_t i=0; i<fLay3Ndet; i++)
 120     fLay3sensorZPos[i] = -fSegmentLength*fLay3Ndet/2.+fSegmentLength/2.+i*fSegmentLength;
 121
 122   for (Int_t i=0; i<fLay4Ndet; i++)
 123     fLay4sensorZPos[i] = -fSegmentLength*fLay4Ndet/2.+fSegmentLength/2.+i*fSegmentLength;
 124
 125 };
 126 //________________________________________________________________________
 127 TGeoCombiTrans *AliITSv11GeometrySDD::
 128 CreateCombiTrans(const char *name, Double_t dy, Double_t dz, Double_t dphi) {
 129     //
 130     // return the TGeoCombiTrans which make a translation in y and z
 131     // and a rotation in phi in the global coord system
 132     //
 133
 134     TGeoTranslation t1(dy*CosD(90.+dphi),dy*SinD(90.+dphi), dz);
 135     TGeoRotation r1("",0.,0.,dphi);
 136
 137     TGeoCombiTrans *combiTrans1 = new TGeoCombiTrans(name);
 138     combiTrans1->SetTranslation(t1);
 139     combiTrans1->SetRotation(r1);
 140     return combiTrans1;
 141 };
 142 //________________________________________________________________________
 143 void AliITSv11GeometrySDD::AddTranslationTotCombiTrans(TGeoCombiTrans* ct,
 144                                                        Double_t dx,
 145                                                        Double_t dy,
 146                                                        Double_t dz) {
 147     // Add a dx,dy,dz translation to the initial TGeoCombiTrans
 148     const Double_t *vect = ct->GetTranslation();
 149     Double_t newVect[3];
 150     newVect[0] = vect[0]+dx;
 151     newVect[1] = vect[1]+dy;
 152     newVect[2] = vect[2]+dz;
 153     ct->SetTranslation(newVect);
 154 };
 155 //________________________________________________________________________
 156 void AliITSv11GeometrySDD::Layer3(TGeoVolume *Moth) {
 157     // Insert the layer 3 in the mother volume. This is a virtual volume
 158     // containing ladders of layer 3 and the supporting rings
 159
 160     TGeoTube *virtualLayer3Shape = new TGeoTube("ITSsddLayer3Shape",
 161                                        fLay3Rmin,fLay3Rmax,fLay3Length*0.5);
 162     TGeoMedium *airSDD = gGeoManager->GetMedium("ITSsddAir");
 163     TGeoVolume *virtualLayer3 = new TGeoVolume("ITSsddLayer3",
 164                                                virtualLayer3Shape, airSDD);
 165     TGeoVolume *lay3Ladder = CreateLay3Ladder();
 166     TGeoVolume *lay3Detectors = CreateLay3Detectors();
 167
 168     Double_t dPhi = 360./fLay3Nladd;
 169     Double_t detBoxThickness = fLadWaferSep + 2*fWaferThickness;
 170     // placing virtual ladder and detectors volumes following ladder
 171     // ordering convention
 172     char rotName[20];
 173     Int_t iLaddMin = 0;
 174     Int_t iLaddMax = fLay3Nladd;
 175     if ((fAddOnlyLadder3>=0)&&(fAddOnlyLadder3<fLay3Nladd)) {
 176         iLaddMin = fAddOnlyLadder3;
 177         iLaddMax = fAddOnlyLadder3+1;
 178     }
 179     for (Int_t iLadd = iLaddMin; iLadd < iLaddMax; iLadd++) {
 180         sprintf(rotName, "ITSsddLay3Ladd%i",iLadd);
 181         Double_t minRadiusLadBox = fLay3LaddShortRadius;
 182         if (iLadd%2 != 0) minRadiusLadBox = fLay3LaddLongRadius;
 183         minRadiusLadBox += ((TGeoBBox*)lay3Ladder->GetShape())->GetDY();
 184
 185         TGeoCombiTrans *ctLadd = CreateCombiTrans(rotName,minRadiusLadBox,0,
 186                                                   -90+iLadd*dPhi);
 187         virtualLayer3->AddNode(lay3Ladder,iLadd,ctLadd);
 188         sprintf(rotName, "ITSsddLay3DetBox%i",iLadd);
 189         Double_t minRadiusDetBox = fLay3DetShortRadius;
 190         if (iLadd%2 != 0) minRadiusDetBox = fLay3DetLongRadius;
 191         minRadiusDetBox += detBoxThickness/2;
 192         TGeoCombiTrans *ctDet = CreateCombiTrans(rotName, minRadiusDetBox,0,
 193                                                  -90+iLadd*dPhi);
 194         virtualLayer3->AddNode(lay3Detectors, iLadd, ctDet);
 195     }
 196     virtualLayer3->SetVisibility(kFALSE);
 197     Moth->AddNode(virtualLayer3,1,0);
 198 };
 199 //________________________________________________________________________
 200 TGeoVolume *AliITSv11GeometrySDD::CreateLay3Ladder() {
 201     // return a box volume containing the CF ladder
 202     TGeoVolume *laddSegment = CreateLadderSegment();
 203     TGeoBBox *ladBox = new TGeoBBox("ITSsddLadBox",
 204                                ((TGeoBBox*)laddSegment->GetShape())->GetDX(),
 205                                ((TGeoBBox*)laddSegment->GetShape())->GetDY(),
 206                                     //dX,dY = dX,dY of the segment
 207                                fLay3LadderLength/2);
 208     TGeoMedium *airSDD = gGeoManager->GetMedium("ITSsddAir");
 209     TGeoVolume *virtualLadder = new TGeoVolume("ITSsddLadder",ladBox, airSDD);
 210     Double_t segmentLength = fSegmentLength;
 211     char transName[20];
 212     // placing virtual ladder segment following detector ordering convention
 213     //=======================================================================
 214     Int_t iSegmentMin = 1;
 215     Int_t iSegmentMax = fLay3Ndet;
 216     if (fAddOnlySegment) {
 217         iSegmentMin = fAddOnlySegment;
 218         iSegmentMax = fAddOnlySegment;
 219     }
 220     for (Int_t iSegment = iSegmentMin; iSegment <= iSegmentMax; iSegment++ ) {
 221         sprintf(transName, "ITSsddLay3LaddSeg%i", iSegment);
 222         Double_t segmentPos = segmentLength*(3-iSegment) + segmentLength/2;
 223         TGeoTranslation *segTr = new TGeoTranslation(transName,0,0,segmentPos);
 224         virtualLadder->AddNode(laddSegment, iSegment, segTr);
 225     }
 226     // putting virtual volume corresponding to the end of ladder
 227     //=======================================================================
 228     Double_t endLength = (fLay3LadderLength-fLay3Ndet*fSegmentLength)/2.;
 229     TGeoVolume *endLadder = CreateEndLadder( endLength );
 230     TGeoTranslation *endTrZPos = new TGeoTranslation("ITSsddEndTrZPos",0,0,
 231                                    fSegmentLength*(fLay3Ndet/2)+endLength/2.);
 232     //Euler rotation : about Z, then new X, then new Z
 233     TGeoRotation *endZNegRot = new TGeoRotation("",90, 180, -90);
 234     TGeoCombiTrans *endTrZNeg = new TGeoCombiTrans(0,0,
 235                     -fSegmentLength*(fLay3Ndet/2)-endLength/2., endZNegRot);
 236     if ((fAddOnlySegment==0)||(fAddOnlySegment==1))
 237         virtualLadder->AddNode(endLadder, 1, endTrZPos);
 238     if ((fAddOnlySegment==0)||(fAddOnlySegment==fLay3Ndet))
 239         virtualLadder->AddNode(endLadder, 2, endTrZNeg);
 240     virtualLadder->SetVisibility(kFALSE);
 241     return virtualLadder;
 242 };
 243 //________________________________________________________________________
 244 TGeoArb8 *AliITSv11GeometrySDD::CreateLadderSide(Double_t dz,Double_t angle,
 245                           Double_t xSign,Double_t L, Double_t H, Double_t l) {
 246     // Create one half of the V shape corner of CF ladder
 247
 248     TGeoArb8 *cfLaddSide = new TGeoArb8(dz);
 249     cfLaddSide->SetVertex(0, 0,0);
 250     cfLaddSide->SetVertex(1, 0, -H);
 251     cfLaddSide->SetVertex(2,xSign*(L*TMath::Sin(angle)-l*TMath::Cos(angle)),
 252                           -L*TMath::Cos(angle)-l*TMath::Sin(angle));
 253     cfLaddSide->SetVertex(3,xSign*L*TMath::Sin(angle),-L*TMath::Cos(angle));
 254     cfLaddSide->SetVertex(4, 0,0);
 255     cfLaddSide->SetVertex(5, 0, -H);
 256     cfLaddSide->SetVertex(6,xSign*(L*TMath::Sin(angle)-l*TMath::Cos(angle)),
 257                           -L*TMath::Cos(angle)-l*TMath::Sin(angle));
 258     cfLaddSide->SetVertex(7,xSign*L*TMath::Sin(angle),-L*TMath::Cos(angle));
 259     return cfLaddSide;
 260 };
 261 //________________________________________________________________________
 262 void AliITSv11GeometrySDD::AddLadderCFstruct(Double_t dy, TGeoVolume* vol) {
 263     // fill a volume (segment) with the CF structure of a ladder
 264
 265     TGeoMedium *carbonFiberLadderStruct = gGeoManager->GetMedium(
 266                                                         "ITSsddCarbonFiber");
 267     Double_t segmentLength = fSegmentLength;
 268     Double_t triangleHeight = fLadderHeight - fLadderBeamRadius;
 269     Double_t halfTheta = TMath::ATan( 0.5*fLadderWidth/triangleHeight );
 270     Double_t beta = (TMath::Pi()-2.*halfTheta)/4.;
 271     Double_t alpha = TMath::Pi()*3./4. - halfTheta/2.;
 272     Int_t colorCarbonFiber = 4;
 273
 274     //--- The 3 V shape corners of the Carbon Fiber Ladder
 275     //--- the top V
 276     TGeoArb8 *cfLaddTop1 = CreateLadderSide(segmentLength/2., halfTheta, -1,
 277                                             fLadderLa, fLadderHa, fLadderl);
 278     TGeoVolume *cfLaddTopVol1 = new TGeoVolume("ITSsddCFladdTopCornerVol1",
 279                                            cfLaddTop1,carbonFiberLadderStruct);
 280     cfLaddTopVol1->SetLineColor(colorCarbonFiber);
 281     TGeoArb8 *cfLaddTop2 = CreateLadderSide(segmentLength/2., halfTheta, 1,
 282                                             fLadderLa, fLadderHa, fLadderl);
 283     TGeoVolume *cfLaddTopVol2 = new TGeoVolume("ITSsddCFladdTopCornerV2",
 284                                            cfLaddTop2,carbonFiberLadderStruct);
 285     cfLaddTopVol2->SetLineColor(colorCarbonFiber);
 286     TGeoTranslation *trTop1 = new TGeoTranslation(0, fLadderHeight/2+dy, 0);
 287     vol->AddNode(cfLaddTopVol1, 1, trTop1);
 288     vol->AddNode(cfLaddTopVol2, 1, trTop1);
 289     //--- the 2 side V
 290     TGeoArb8 *cfLaddSide1 = CreateLadderSide( segmentLength/2., beta, -1,
 291                                               fLadderLb, fLadderHb, fLadderl);
 292     TGeoVolume *cfLaddSideVol1 = new TGeoVolume("ITSsddCFladdSideCornerV1",
 293                                          cfLaddSide1,carbonFiberLadderStruct);
 294     cfLaddSideVol1->SetLineColor(colorCarbonFiber);
 295     TGeoArb8 *cfLaddSide2 = CreateLadderSide( segmentLength/2., beta, 1,
 296                                               fLadderLb, fLadderHb, fLadderl);
 297     TGeoVolume *cfLaddSideVol2 = new TGeoVolume("ITSsddCFladdSideCornerV2",
 298                                          cfLaddSide2,carbonFiberLadderStruct);
 299     cfLaddSideVol2->SetLineColor(colorCarbonFiber);
 300
 301     Double_t dYTranslation = fLadderHeight/2. -
 302                       0.5*fLadderWidth*TMath::Tan(beta) - fLadderBeamRadius;
 303     // because center of the triangle doesn't correspond to virtual vol. center
 304     Double_t distCenterSideDown =  0.5*fLadderWidth/TMath::Cos(beta);
 305     TGeoCombiTrans *ctSideR = CreateCombiTrans("", distCenterSideDown, 0,
 306                                                alpha*TMath::RadToDeg());
 307     AddTranslationTotCombiTrans(ctSideR, 0, -dYTranslation+dy, 0);
 308     TGeoCombiTrans *ctSideL = CreateCombiTrans("", distCenterSideDown,0,
 309                                                -alpha*TMath::RadToDeg());
 310     AddTranslationTotCombiTrans(ctSideL, 0, -dYTranslation+dy, 0);
 311     vol->AddNode(cfLaddSideVol1, 1, ctSideR);
 312     vol->AddNode(cfLaddSideVol2, 1, ctSideR);
 313     vol->AddNode(cfLaddSideVol1, 2, ctSideL);
 314     vol->AddNode(cfLaddSideVol2, 2, ctSideL);
 315     //--- The beams
 316     // Beams on the sides
 317     Double_t beamPhiPrime = TMath::ASin(1./TMath::Sqrt( (1+TMath::Sin(2*beta)*
 318                 TMath::Sin(2*beta)/(TanD(fBeamSidePhi)*TanD(fBeamSidePhi))) ));
 319     if(GetDebug(1)) cout<<"Phi prime = "<<beamPhiPrime*TMath::RadToDeg()<<endl;
 320     Double_t beamLength = TMath::Sqrt( fLadderHeight*fLadderHeight/
 321                            (TMath::Sin(beamPhiPrime)*TMath::Sin(beamPhiPrime))
 322                                +fLadderWidth*fLadderWidth/4.)-fLadderLa/2-fLadderLb/2;
 323     TGeoTubeSeg *sideBeam = new TGeoTubeSeg(0,fLadderBeamRadius,beamLength/2.,
 324                                           0, 180);
 325     TGeoVolume *cfSideBeamVol = new TGeoVolume("ITSsddCFSideBeamVol", sideBeam,
 326                                                carbonFiberLadderStruct);
 327     cfSideBeamVol->SetLineColor(colorCarbonFiber);
 328     //Euler rotation : about Z, then new X, then new Z
 329     TGeoRotation *beamRot1 = new TGeoRotation("",90-2.*beta*TMath::RadToDeg(),
 330                                          -beamPhiPrime*TMath::RadToDeg(),-90);
 331     TGeoCombiTrans *beamTransf1 = new TGeoCombiTrans(0.5*triangleHeight*
 332     TMath::Tan(halfTheta),fLadderBeamRadius/2.+dy,-3*segmentLength/8,beamRot1);
 333     TGeoCombiTrans *beamTransf2 = new TGeoCombiTrans(0.5*triangleHeight*
 334        TMath::Tan(halfTheta),fLadderBeamRadius/2.+dy,segmentLength/8,beamRot1);
 335     TGeoRotation *beamRot2 = new TGeoRotation("",90-2.*beta*TMath::RadToDeg(),
 336                                             beamPhiPrime*TMath::RadToDeg(), -90);
 337     TGeoCombiTrans *beamTransf3 = new TGeoCombiTrans(0.5*triangleHeight*
 338      TMath::Tan(halfTheta),fLadderBeamRadius/2.+dy,-segmentLength/8,beamRot2);
 339     TGeoCombiTrans *beamTransf4 = new TGeoCombiTrans(0.5*triangleHeight*
 340      TMath::Tan(halfTheta),fLadderBeamRadius/2.+dy,3*segmentLength/8,beamRot2);
 341     TGeoRotation *beamRot3 = new TGeoRotation("",90+2.*beta*TMath::RadToDeg(),
 342                                             beamPhiPrime*TMath::RadToDeg(), -90);
 343     TGeoCombiTrans *beamTransf5 = new TGeoCombiTrans(-0.5*triangleHeight*
 344                                 TMath::Tan(halfTheta),fLadderBeamRadius/2.+dy,
 345                                               -3*segmentLength/8,beamRot3);
 346     TGeoCombiTrans *beamTransf6 = new TGeoCombiTrans(-0.5*triangleHeight*
 347        TMath::Tan(halfTheta),fLadderBeamRadius/2.+dy,segmentLength/8,beamRot3);
 348     TGeoRotation *beamRot4 = new TGeoRotation("",90+2.*beta*TMath::RadToDeg(),
 349                                             -beamPhiPrime*TMath::RadToDeg(), -90);
 350     TGeoCombiTrans *beamTransf7 = new TGeoCombiTrans(-0.5*triangleHeight*
 351       TMath::Tan(halfTheta),fLadderBeamRadius/2.+dy,-segmentLength/8,beamRot4);
 352     TGeoCombiTrans *beamTransf8 = new TGeoCombiTrans(-0.5*triangleHeight*
 353      TMath::Tan(halfTheta),fLadderBeamRadius/2.+dy,3*segmentLength/8,beamRot4);
 354
 355     vol->AddNode(cfSideBeamVol, 1, beamTransf1);
 356     vol->AddNode(cfSideBeamVol, 2, beamTransf2);
 357     vol->AddNode(cfSideBeamVol, 3, beamTransf3);
 358     vol->AddNode(cfSideBeamVol, 4, beamTransf4);
 359     vol->AddNode(cfSideBeamVol, 5, beamTransf5);
 360     vol->AddNode(cfSideBeamVol, 6, beamTransf6);
 361     vol->AddNode(cfSideBeamVol, 7, beamTransf7);
 362     vol->AddNode(cfSideBeamVol, 8, beamTransf8);
 363     //--- Beams of the bottom
 364     TGeoTubeSeg *bottomBeam1 = new TGeoTubeSeg(0, fLadderBeamRadius,
 365                                              fLadderWidth/2.-fLadderLb/3, 0, 180);
 366     TGeoVolume *bottomBeam1Vol = new TGeoVolume("ITSsddBottomBeam1Vol",
 367                                      bottomBeam1, carbonFiberLadderStruct);
 368     bottomBeam1Vol->SetLineColor(colorCarbonFiber);
 369
 370     TGeoRotation *bottomBeamRot1 = new TGeoRotation("",90, 90, 90);
 371     TGeoCombiTrans *bottomBeamTransf1 = new TGeoCombiTrans(0,
 372                     -(fLadderHeight/2-fLadderBeamRadius)+dy,0, bottomBeamRot1);
 373     vol->AddNode(bottomBeam1Vol, 1, bottomBeamTransf1);
 374     TGeoTubeSeg *bottomBeam2 = new TGeoTubeSeg(0, fLadderBeamRadius,
 375                                                        fLadderWidth/2.-fLadderLb/3, 0, 90);
 376     TGeoVolume *bottomBeam2Vol = new TGeoVolume("ITSsddBottomBeam2Vol",
 377                                 bottomBeam2, carbonFiberLadderStruct);
 378     bottomBeam2Vol->SetLineColor(colorCarbonFiber);
 379     TGeoCombiTrans *bottomBeamTransf2 = new TGeoCombiTrans(0,
 380                                      -(fLadderHeight/2-fLadderBeamRadius)+dy,
 381                                      -segmentLength/2, bottomBeamRot1);
 382     TGeoRotation *bottomBeamRot2 = new TGeoRotation("",-90, 90, -90);
 383     TGeoCombiTrans *bottomBeamTransf3 = new TGeoCombiTrans(0,
 384                                     -(fLadderHeight/2-fLadderBeamRadius)+dy,
 385                                                          segmentLength/2, bottomBeamRot2);
 386     vol->AddNode(bottomBeam2Vol, 1, bottomBeamTransf2);
 387     vol->AddNode(bottomBeam2Vol, 2, bottomBeamTransf3);
 388     TGeoTubeSeg *bottomBeam3 = new TGeoTubeSeg(0, fLadderBeamRadius,
 389                             0.5*fLadderWidth/SinD(fBottomBeamAngle)-fLadderLb/3,0,180);
 390     TGeoVolume *bottomBeam3Vol = new TGeoVolume("ITSsddBottomBeam3Vol",
 391                   bottomBeam3, carbonFiberLadderStruct);
 392     bottomBeam3Vol->SetLineColor(colorCarbonFiber);
 393     //bottomBeam3Vol->SetLineColor(2);
 394     // be careful on the next 2 beams : when "reading" from -z to +z and
 395     // from the bottom of the ladder,
 396     // it should draw a Lambda, and not a V
 397     TGeoRotation *bottomBeamRot4 = new TGeoRotation("", -90, fBottomBeamAngle,
 398                                                     -90);
 399     TGeoCombiTrans *bottomBeamTransf4 = new TGeoCombiTrans(0,
 400       -(fLadderHeight/2-fLadderBeamRadius)+dy,-segmentLength/4,bottomBeamRot4);
 401     TGeoRotation *bottomBeamRot5 = new TGeoRotation("",-90,-fBottomBeamAngle,
 402                                                     -90);
 403     TGeoCombiTrans *bottomBeamTransf5 = new TGeoCombiTrans(0,
 404      -(fLadderHeight/2-fLadderBeamRadius)+dy,segmentLength/4, bottomBeamRot5);
 405     vol->AddNode(bottomBeam3Vol, 1, bottomBeamTransf4);
 406     vol->AddNode(bottomBeam3Vol, 2, bottomBeamTransf5);
 407 };
 408 //________________________________________________________________________
 409 TGeoVolume* AliITSv11GeometrySDD::CreateHybrid() {
 410     // return a box containing the front-end hybrid
 411     TGeoBBox *hybridBox = new TGeoBBox("ITSsddHybridBox",fHybridWidth/2,0.3/2,
 412                                        fHybridLength/2); // <===== 0.3 tempo
 413     TGeoMedium *airSDD = gGeoManager->GetMedium("ITSsddAir");
 414     TGeoVolume *VirtualHybrid =new TGeoVolume("ITSsddHybrid",hybridBox,airSDD);
 415
 416     VirtualHybrid->SetVisibility(kFALSE);
 417     return VirtualHybrid;
 418 };
 419 //________________________________________________________________________
 420 TGeoVolume* AliITSv11GeometrySDD::CreateLadderSegment() {
 421     // Return a box volume containing a segment of a ladder.
 422
 423     TGeoMedium *airSDD = gGeoManager->GetMedium("ITSsddAir");
 424
 425     Double_t tDY = -0.5; //space left on top of the ladder
 426     Double_t segmentLength = fSegmentLength;
 427
 428     TGeoBBox *segBox = new TGeoBBox("ITSsddSegBox",
 429                                     (fLadderWidth+fPinSuppWidth)/2,
 430                                     fLadderHeight/2+TMath::Abs(tDY),
 431                                     segmentLength/2);
 432     TGeoVolume *VirtualSeg = new TGeoVolume("ITSsddSegment",segBox, airSDD);
 433     // the carbon fiber structure :
 434     AddLadderCFstruct(tDY, VirtualSeg);
 435     // the 2 hybrids :
 436     TGeoVolume *Hybrid = CreateHybrid();
 437     Double_t hybDx = ((TGeoBBox*)Hybrid->GetShape())->GetDX();
 438     Double_t hybDy = ((TGeoBBox*)Hybrid->GetShape())->GetDY();
 439     Double_t halfDiag = TMath::Sqrt(hybDx*hybDx+hybDy*hybDy);
 440     Double_t theta = 50;  //angle in the transverse plane of hybrids
 441     // laying on the CF structure  // <========== 50° tempo
 442     Double_t thetaPrim = theta*TMath::DegToRad()+TMath::ATan(hybDy/hybDx);
 443     TGeoRotation *HybridRot1 = new TGeoRotation("",   90-theta, 0, 0);
 444     TGeoRotation *HybridRot2 = new TGeoRotation("", -(90-theta), 0, 0);
 445     Double_t hybZ = 0;
 446     Double_t hybY = fLadderHeight/2-halfDiag*TMath::Cos(thetaPrim)+tDY;
 447     Double_t hybX = halfDiag*TMath::Sin(thetaPrim);
 448     TGeoCombiTrans *HybTransf1 = new TGeoCombiTrans(-hybX,hybY,hybZ,
 449                                                     HybridRot1);
 450     VirtualSeg->AddNode(Hybrid, 1, HybTransf1);
 451     TGeoCombiTrans *HybTransf2 = new TGeoCombiTrans(hybX,hybY,hybZ,HybridRot2);
 452     VirtualSeg->AddNode(Hybrid, 2, HybTransf2);
 453     //**********************************
 454     TGeoVolume *pinSupport = CreatePinSupport(0);
 455     VirtualSeg->AddNode(pinSupport, 1, 0);
 456     VirtualSeg->SetVisibility(kFALSE);
 457     return VirtualSeg;
 458 };
 459 //________________________________________________________________________
 460 TGeoVolume* AliITSv11GeometrySDD::CreatePinSupport(Double_t rotY) {
 461     //medium = ryton ? To code !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 462
 463     TGeoMedium *rytonSDD = gGeoManager->GetMedium("ITSsddStaselite4411w");
 464     TGeoCone *cone = new TGeoCone("ITSsddPinSuppCone",fPinSuppHeight/2.,
 465                                   0,fPinSuppRmax,0,fPinSuppRmax-
 466                                   fPinSuppHeight*TanD(fPinSuppConeAngle) );
 467     TGeoBBox *tong = new TGeoBBox("ITSsddPinSuppTong",fPinSuppRmax,
 468                                   fPinSuppLength/2.,fPinSuppThickness/2.);
 469     TGeoTube *hole = new TGeoTube("ITSsddPinSuppHole",0,fPinR,
 470                                   fPinSuppHeight/2.);
 471     rotY = 0.0; // Remove compiler warning.
 472     if(GetDebug(3)){
 473         cone->InspectShape();
 474         tong->InspectShape();
 475         hole->InspectShape();
 476     }
 477
 478     TGeoTranslation *tongTrans = new TGeoTranslation("ITSsddPinSuppTongTr",0,
 479                    fPinSuppLength/2.,-fPinSuppHeight/2.+fPinSuppThickness/2.);
 480     tongTrans->RegisterYourself();
 481     TGeoCompositeShape *pinSupportShape = new TGeoCompositeShape(
 482                "ITSssdPinSupportShape","(ITSsddPinSuppCone+"
 483                "ITSsddPinSuppTong:ITSsddPinSuppTongTr)-ITSsddPinSuppHole");
 484
 485     TGeoVolume *pinSupport = new TGeoVolume("ITSssdPinSupport",pinSupportShape,
 486                                             rytonSDD);
 487     return pinSupport;
 488     // include the pin itself !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 489     // le centre de rotation, translation est le centre du cone
 490     // (puisque celui-ci n'a pas bouger dans la composition)
 491 };
 492 //________________________________________________________________________
 493 TGeoVolume* AliITSv11GeometrySDD::CreateEndLadder(Double_t length) {
 494     // Return a box volume containing a end of a CF ladder.
 495     Double_t tDY = -0.5; //space left on top of the ladder
 496     TGeoMedium *airSDD = gGeoManager->GetMedium("ITSsddAir");
 497     TGeoMedium *carbonFiberLadderStruct = gGeoManager->GetMedium(
 498                                                        "ITSsddCarbonFiber");
 499     Double_t segmentLength = fSegmentLength;
 500     Double_t topCornerLength = fSegmentLength/2.-fLay4LaddTopCornerEnd;
 501
 502     TGeoBBox *endBox = new TGeoBBox("ITSsddEndLaddBox",
 503                                     //(fLadderWidth+fPinSuppWidth)/2,
 504                                     (fLadderWidth)/2,
 505                                     fLadderHeight/2+TMath::Abs(tDY),
 506                                     length/2);
 507     TGeoVolume *virtualEnd = new TGeoVolume("ITSsddEnd",endBox, airSDD);
 508     //**********************************
 509     // coding real matter :
 510     //**********************************
 511     Double_t triangleHeight = fLadderHeight - fLadderBeamRadius;
 512     Double_t halfTheta = TMath::ATan( 0.5*fLadderWidth/triangleHeight );
 513     Double_t beta = (TMath::Pi()-2.*halfTheta)/4.;
 514     Double_t alpha = TMath::Pi()*3./4. - halfTheta/2.;
 515     Int_t colorCarbonFiber = 4;
 516     //--- The 3 V shape corners of the Carbon Fiber Ladder
 517     //--- the top V
 518     TGeoArb8 *cfLaddTop1 = CreateLadderSide( topCornerLength/2., halfTheta, -1,
 519                                              fLadderLa, fLadderHa, fLadderl);
 520     TGeoVolume *cfLaddTopVol1 = new TGeoVolume("ITSsddCFladdTopCornerVol1",
 521                                           cfLaddTop1,carbonFiberLadderStruct);
 522     cfLaddTopVol1->SetLineColor(colorCarbonFiber);
 523     TGeoArb8 *cfLaddTop2 = CreateLadderSide( topCornerLength/2., halfTheta, 1,
 524                                              fLadderLa, fLadderHa, fLadderl);
 525     TGeoVolume *cfLaddTopVol2 = new TGeoVolume("ITSsddCFladdTopCornerV2",
 526                                         cfLaddTop2,carbonFiberLadderStruct);
 527     cfLaddTopVol2->SetLineColor(colorCarbonFiber);
 528     TGeoTranslation *trTop1 = new TGeoTranslation(0, fLadderHeight/2+tDY,
 529                                                -(length-topCornerLength)/2.);
 530     virtualEnd->AddNode(cfLaddTopVol1, 1, trTop1);
 531     virtualEnd->AddNode(cfLaddTopVol2, 1, trTop1);
 532     //--- the 2 side V
 533     TGeoArb8 *cfLaddSide1 = CreateLadderSide( length/2., beta, -1,
 534                                               fLadderLb, fLadderHb, fLadderl);
 535     TGeoVolume *cfLaddSideVol1 = new TGeoVolume("ITSsddCFladdSideCornerV1",
 536                                           cfLaddSide1,carbonFiberLadderStruct);
 537     cfLaddSideVol1->SetLineColor(colorCarbonFiber);
 538     TGeoArb8 *cfLaddSide2 = CreateLadderSide( length/2., beta, 1,
 539                                               fLadderLb, fLadderHb, fLadderl);
 540     TGeoVolume *cfLaddSideVol2 = new TGeoVolume("ITSsddCFladdSideCornerV2",
 541                                           cfLaddSide2,carbonFiberLadderStruct);
 542     cfLaddSideVol2->SetLineColor(colorCarbonFiber);
 543     Double_t dYTranslation = ( fLadderHeight/2. - 0.5*fLadderWidth*
 544                                TMath::Tan(beta)- fLadderBeamRadius );
 545     // because center of the triangle doesn't correspond to virtual vol. center
 546     Double_t distCenterSideDown =  0.5*fLadderWidth/TMath::Cos(beta);
 547     TGeoCombiTrans *ctSideR = CreateCombiTrans("", distCenterSideDown, 0,
 548                                                alpha*TMath::RadToDeg());
 549     AddTranslationTotCombiTrans(ctSideR, 0, -dYTranslation+tDY, 0);
 550     TGeoCombiTrans *ctSideL = CreateCombiTrans("", distCenterSideDown, 0,
 551                                                -alpha*TMath::RadToDeg());
 552     AddTranslationTotCombiTrans(ctSideL, 0, -dYTranslation+tDY, 0);
 553     virtualEnd->AddNode(cfLaddSideVol1, 1, ctSideR);
 554     virtualEnd->AddNode(cfLaddSideVol2, 1, ctSideR);
 555     virtualEnd->AddNode(cfLaddSideVol1, 2, ctSideL);
 556     virtualEnd->AddNode(cfLaddSideVol2, 2, ctSideL);
 557     //--- The beams
 558     // Beams on the sides
 559     Double_t beamPhiPrime = TMath::ASin(1./TMath::Sqrt( (1+TMath::Sin(2*beta)*
 560                 TMath::Sin(2*beta)/(TanD(fBeamSidePhi)*TanD(fBeamSidePhi))) ));
 561     if(GetDebug(3)) cout<<"Phi prime = "<<beamPhiPrime*TMath::RadToDeg()<<endl;
 562      Double_t beamLength = TMath::Sqrt( fLadderHeight*fLadderHeight/
 563                                      (TMath::Sin(beamPhiPrime)*TMath::Sin(beamPhiPrime))
 564                                    +fLadderWidth*fLadderWidth/4.)-fLadderLa/2-fLadderLb/2;
 565      TGeoTubeSeg *sideBeam = new TGeoTubeSeg(0, fLadderBeamRadius,
 566                                              beamLength/2., 0, 180);
 567      TGeoVolume *cfSideBeamVol = new TGeoVolume("ITSsddCFSideBeamVol",
 568                                       sideBeam, carbonFiberLadderStruct);
 569      cfSideBeamVol->SetLineColor(colorCarbonFiber);
 570      //Euler rotation : about Z, then new X, then new Z
 571      TGeoRotation *beamRot1 = new TGeoRotation("",90-2.*beta*TMath::RadToDeg(),
 572                                                         -beamPhiPrime*TMath::RadToDeg(), -90);
 573      TGeoCombiTrans *beamTransf1 = new TGeoCombiTrans(0.5*triangleHeight*
 574                    TMath::Tan(halfTheta),fLadderBeamRadius/2.+tDY,
 575                                                    -length/2+segmentLength/8,beamRot1);
 576      TGeoRotation *beamRot2 = new TGeoRotation("",90-2.*beta*TMath::RadToDeg(),
 577                                             beamPhiPrime*TMath::RadToDeg(), -90);
 578      TGeoCombiTrans *beamTransf3 = new TGeoCombiTrans(0.5*triangleHeight*
 579                      TMath::Tan(halfTheta),fLadderBeamRadius/2.+tDY,
 580                                                    -length/2+3*segmentLength/8,beamRot2);
 581      TGeoRotation *beamRot3 = new TGeoRotation("",90+2.*beta*TMath::RadToDeg(),
 582                                             beamPhiPrime*TMath::RadToDeg(), -90);
 583      TGeoCombiTrans *beamTransf5 = new TGeoCombiTrans(-0.5*triangleHeight*
 584                           TMath::Tan(halfTheta),fLadderBeamRadius/2.+tDY,
 585                                                    -length/2+segmentLength/8,beamRot3);
 586      TGeoRotation *beamRot4 = new TGeoRotation("",90+2.*beta*TMath::RadToDeg(),
 587                                             -beamPhiPrime*TMath::RadToDeg(), -90);
 588      TGeoCombiTrans *beamTransf7 = new TGeoCombiTrans(-0.5*triangleHeight*
 589             TMath::Tan(halfTheta),fLadderBeamRadius/2.+tDY,
 590                                                    -length/2+3*segmentLength/8,beamRot4);
 591      virtualEnd->AddNode(cfSideBeamVol, 1, beamTransf1);
 592      virtualEnd->AddNode(cfSideBeamVol, 2, beamTransf3);
 593      virtualEnd->AddNode(cfSideBeamVol, 3, beamTransf5);
 594      virtualEnd->AddNode(cfSideBeamVol, 4, beamTransf7);
 595      //--- Beams of the bottom
 596      TGeoTubeSeg *bottomBeam1 = new TGeoTubeSeg(0, fLadderBeamRadius,
 597                                              fLadderWidth/2.-fLadderLb/3, 0, 180);
 598      TGeoVolume *bottomBeam1Vol = new TGeoVolume("ITSsddBottomBeam1Vol",
 599                                       bottomBeam1, carbonFiberLadderStruct);
 600      bottomBeam1Vol->SetLineColor(colorCarbonFiber);
 601      TGeoRotation *bottomBeamRot1 = new TGeoRotation("",90, 90, 90);
 602      TGeoCombiTrans *bottomBeamTransf1 = new TGeoCombiTrans(0,
 603                             -(fLadderHeight/2-fLadderBeamRadius)+tDY,
 604                                                  -length/2+fSegmentLength/2, bottomBeamRot1);
 605      virtualEnd->AddNode(bottomBeam1Vol, 1, bottomBeamTransf1);
 606      TGeoTubeSeg *bottomBeam2 = new TGeoTubeSeg(0, fLadderBeamRadius,
 607                                              fLadderWidth/2.-fLadderLb/3, 0, 90);
 608      TGeoVolume *bottomBeam2Vol = new TGeoVolume("ITSsddBottomBeam2Vol",
 609                                    bottomBeam2, carbonFiberLadderStruct);
 610      bottomBeam2Vol->SetLineColor(colorCarbonFiber);
 611      TGeoCombiTrans *bottomBeamTransf2 = new TGeoCombiTrans(0,
 612            -(fLadderHeight/2-fLadderBeamRadius)+tDY,-length/2, bottomBeamRot1);
 613      virtualEnd->AddNode(bottomBeam2Vol, 1, bottomBeamTransf2);
 614      //**********************************
 615      virtualEnd->SetVisibility(kFALSE);
 616      return virtualEnd;
 617 };
 618 //________________________________________________________________________
 619 TGeoVolume* AliITSv11GeometrySDD::CreateSDDsensor() {
 620     // return a box containing the SDD sensor
 621
 622     TGeoBBox *sensorBox = new TGeoBBox("ITSsddSensorBox",
 623                                   fWaferWidth/2, fWaferThickness/2,fWaferLength/2);
 624     TGeoMedium *airSDD = gGeoManager->GetMedium("ITSsddAir");
 625     TGeoVolume *virtualSensor =new TGeoVolume("ITSsddSensor",sensorBox,airSDD);
 626
 627     //virtualSensor->SetVisibility(kFALSE);
 628     return virtualSensor;
 629 };
 630 //________________________________________________________________________
 631 TGeoVolume *AliITSv11GeometrySDD::CreateLay3Detectors() {
 632     // return a box volume containing the detectors
 633
 634     TGeoBBox *detBox = new TGeoBBox("ITSssdDetBox3",
 635                                     fWaferWidth/2,
 636                                     (fLadWaferSep + 2*fWaferThickness)/2,
 637                              fLay3LadderLength*((fLay3Ndet-0.5)/fLay3Ndet)/2);
 638     TGeoMedium *airSDD = gGeoManager->GetMedium("ITSsddAir");
 639     TGeoVolume *virtualDet = new TGeoVolume("ITSsddDet3",detBox, airSDD);
 640     TGeoVolume *vSDD = CreateSDDsensor();
 641     char transName[30];
 642     for (Int_t i=0; i<fLay3Ndet; i++) {
 643         Double_t localZ = fLay3sensorZPos[i];
 644         Double_t localY = fLadWaferSep/2+fWaferThickness/2;
 645         if (i%2!=0)
 646             localY = -localY;
 647         sprintf(transName, "ITSsddLay3SensorPos%i", i+1);
 648         TGeoTranslation *sensorPos = new TGeoTranslation(transName,0,localY,
 649                                                          localZ);
 650         virtualDet->AddNode(vSDD, i+1, sensorPos);
 651     }
 652     virtualDet->SetVisibility(kFALSE);
 653     return virtualDet;
 654 };
 655 //________________________________________________________________________
 656 void AliITSv11GeometrySDD::Layer4(TGeoVolume *Moth) {
 657     // Insert the layer 4 in the mother volume. This is a virtual volume
 658     // containing ladders of layer 4 and the supporting rings
 659
 660     TGeoTube *virtualLayer4Shape =new TGeoTube("ITSsddLayer4Shape",
 661                                         fLay4Rmin,fLay4Rmax,fLay4Length*0.5);
 662     TGeoMedium *airSDD = gGeoManager->GetMedium("ITSsddAir");
 663     TGeoVolume *virtualLayer4 = new TGeoVolume("ITSsddLayer4",
 664                                           virtualLayer4Shape, airSDD);
 665     TGeoVolume *lay4Ladder = CreateLay4Ladder();
 666     TGeoVolume *lay4Detectors = CreateLay4Detectors();
 667     Double_t dPhi = 360./fLay4Nladd;
 668     Double_t detBoxThickness = fLadWaferSep + 2*fWaferThickness;
 669     // placing virtual ladder and detectors volumes following ladder
 670     // ordering convention
 671     char rotName[20];
 672     Int_t iLaddMin = 0;
 673     Int_t iLaddMax = fLay4Nladd;
 674     if ((fAddOnlyLadder4>=0)&&(fAddOnlyLadder4<fLay4Nladd)) {
 675         iLaddMin = fAddOnlyLadder4;
 676         iLaddMax = fAddOnlyLadder4+1;
 677     }
 678     for (Int_t iLadd = iLaddMin; iLadd < iLaddMax; iLadd++) {
 679         sprintf(rotName, "ITSsddLay4Ladd%i",iLadd);
 680         Double_t minRadiusLadBox = fLay4LaddShortRadius;
 681         if (iLadd%2 != 0)
 682             minRadiusLadBox = fLay4LaddLongRadius;
 683         minRadiusLadBox += ((TGeoBBox*)lay4Ladder->GetShape())->GetDY();
 684         TGeoCombiTrans *ctLadd = CreateCombiTrans(rotName, minRadiusLadBox,
 685                                                   0, -90+iLadd*dPhi);
 686         virtualLayer4->AddNode(lay4Ladder, iLadd, ctLadd);
 687         sprintf(rotName, "ITSsddLay4DetBox%i",iLadd);
 688         Double_t minRadiusDetBox = fLay4DetShortRadius;
 689         if (iLadd%2 != 0)
 690             minRadiusDetBox = fLay4DetLongRadius;
 691         minRadiusDetBox += detBoxThickness/2;
 692         TGeoCombiTrans *ctDet = CreateCombiTrans(rotName, minRadiusDetBox,
 693                                                  0, -90+iLadd*dPhi);
 694         virtualLayer4->AddNode(lay4Detectors, iLadd, ctDet);
 695     }
 696     virtualLayer4->SetVisibility(kFALSE);
 697     Moth->AddNode(virtualLayer4,1,0);
 698 };
 699 //________________________________________________________________________
 700 TGeoVolume *AliITSv11GeometrySDD::CreateLay4Ladder() {
 701     // return a box volume containing the CF ladder and all pieces on it
 702
 703     TGeoVolume *laddSegment = CreateLadderSegment();
 704     TGeoBBox *ladBox = new TGeoBBox("ITSsddLadBox",
 705                                ((TGeoBBox*)laddSegment->GetShape())->GetDX(),
 706                                   ((TGeoBBox*)laddSegment->GetShape())->GetDY(),
 707                                   //dX,dY = dX,dY of the segment
 708                                   fLay4LadderLength/2);
 709     TGeoMedium *airSDD = gGeoManager->GetMedium("ITSsddAir");
 710     TGeoVolume *virtualLadder = new TGeoVolume("ITSsddLadder",ladBox, airSDD);
 711     Double_t segmentLength = fSegmentLength;
 712     char transName[20];
 713     // placing virtual ladder segment following detector ordering convention
 714     //=======================================================================
 715     Int_t iSegmentMin = 1;
 716     Int_t iSegmentMax = fLay4Ndet;
 717     if (fAddOnlySegment) {
 718         iSegmentMin = fAddOnlySegment;
 719         iSegmentMax = fAddOnlySegment;
 720     }
 721     for (Int_t iSegment = iSegmentMin; iSegment <= iSegmentMax; iSegment++ ) {
 722         sprintf(transName, "ITSsddLay4LaddSeg%i", iSegment);
 723         Double_t segmentPos = segmentLength*(fLay4Ndet/2-iSegment) +
 724             segmentLength/2;
 725         TGeoTranslation *segTr = new TGeoTranslation(transName,0,0,segmentPos);
 726         virtualLadder->AddNode(laddSegment, iSegment, segTr);
 727     }
 728     // putting virtual volume corresponding to the end of ladder
 729     //=======================================================================
 730     Double_t endLength = (fLay4LadderLength-fLay4Ndet*fSegmentLength)/2.;
 731     TGeoVolume *endLadder = CreateEndLadder( endLength );
 732     TGeoTranslation *endTrZPos =
 733         new TGeoTranslation("ITSsddEndTrZPos",0,0,
 734                             fSegmentLength*(fLay4Ndet/2)+endLength/2.);
 735     //Euler rotation : about Z, then new X, then new Z
 736     TGeoRotation *endZNegRot = new TGeoRotation("",90, 180, -90);
 737     TGeoCombiTrans *endTrZNeg =
 738         new TGeoCombiTrans(0,0,-fSegmentLength*(fLay4Ndet/2)-endLength/2.,
 739                            endZNegRot);
 740     if ((fAddOnlySegment==0)||(fAddOnlySegment==1))
 741         virtualLadder->AddNode(endLadder, 1, endTrZPos);
 742     if ((fAddOnlySegment==0)||(fAddOnlySegment==fLay4Ndet))
 743         virtualLadder->AddNode(endLadder, 2, endTrZNeg);
 744     virtualLadder->SetVisibility(kFALSE);
 745     return virtualLadder;
 746 };
 747 //________________________________________________________________________
 748 TGeoVolume *AliITSv11GeometrySDD::CreateLay4Detectors() {
 749     // return a box volume containing the detectors
 750
 751     TGeoBBox *detBox = new TGeoBBox("ITSssdDetBox4",
 752                                     fWaferWidth/2,
 753                                     (fLadWaferSep + 2*fWaferThickness)/2,
 754                              fLay4LadderLength*((fLay4Ndet-0.5)/fLay4Ndet)/2);
 755     TGeoMedium *airSDD = gGeoManager->GetMedium("ITSsddAir");
 756     TGeoVolume *virtualDet = new TGeoVolume("ITSsddDet4",detBox, airSDD);
 757     TGeoVolume *vSDD = CreateSDDsensor();
 758     char transName[30];
 759     for (Int_t i=0; i<fLay4Ndet; i++) {
 760         Double_t localZ = fLay4sensorZPos[i];
 761         Double_t localY = fLadWaferSep/2+fWaferThickness/2;
 762         if (i%2!=0)
 763             localY = -localY;
 764         sprintf(transName, "ITSsddLay4SensorPos%i", i+1);
 765         TGeoTranslation *sensorPos = new TGeoTranslation(transName,0,localY,
 766                                                          localZ);
 767         virtualDet->AddNode(vSDD, i+1, sensorPos);
 768     }
 769     virtualDet->SetVisibility(kFALSE);
 770     return virtualDet;
 771 };