TPC/AliTPCv2.cxx

   1 /**************************************************************************
   2  * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
   3  *                                                                        *
   4  * Author: The ALICE Off-line Project.                                    *
   5  * Contributors are mentioned in the code where appropriate.              *
   6  *                                                                        *
   7  * Permission to use, copy, modify and distribute this software and its   *
   8  * documentation strictly for non-commercial purposes is hereby granted   *
   9  * without fee, provided that the above copyright notice appears in all   *
  10  * copies and that both the copyright notice and this permission notice   *
  11  * appear in the supporting documentation. The authors make no claims     *
  12  * about the suitability of this software for any purpose. It is          *
  13  * provided "as is" without express or implied warranty.                  *
  14  **************************************************************************/
  15
  16 /* $Id$ */
  17
  18 //
  19 ///////////////////////////////////////////////////////////////////////////////
  20 //                                                                           //
  21 //  Time Projection Chamber version 2 -- detailed TPC and slow simulation    //
  22 //                                                                           //
  23 //Begin_Html
  24 /*
  25 <img src="picts/AliTPCv2Class.gif">
  26 */
  27 //End_Html
  28 //                                                                           //
  29 //                                                                           //
  30 ///////////////////////////////////////////////////////////////////////////////
  31
  32 #include <stdlib.h>
  33
  34 #include <TLorentzVector.h>
  35 #include <TMath.h>
  36 #include <TPDGCode.h>
  37 #include <TVirtualMC.h>
  38 #include <TString.h>
  39 #include <TSystem.h>
  40
  41 #include "AliConst.h"
  42 #include "AliLog.h"
  43 #include "AliMC.h"
  44 #include "AliRun.h"
  45 #include "AliTPCDigitsArray.h"
  46 #include "AliTPCParam.h"
  47 #include "AliTPCParamSR.h"
  48 #include "AliTPCTrackHitsV2.h"
  49 #include "AliTPCv2.h"
  50 #include "TGeoManager.h"
  51 #include "TGeoVolume.h"
  52 #include "TGeoPcon.h"
  53 #include "TGeoTube.h"
  54 #include "TGeoPgon.h"
  55 #include "TGeoTrd1.h"
  56 #include "TGeoCompositeShape.h"
  57 #include "TGeoPara.h"
  58 ClassImp(AliTPCv2)
  59
  60 //_____________________________________________________________________________
  61 AliTPCv2::AliTPCv2(const char *name, const char *title) :
  62   AliTPC(name, title)
  63 {
  64   //
  65   // Standard constructor for Time Projection Chamber version 2
  66   //
  67
  68
  69   SetBufferSize(128000);
  70
  71
  72   if (fTPCParam)
  73      fTPCParam->Write(fTPCParam->GetTitle());
  74 }
  75
  76 //_____________________________________________________________________________
  77 void AliTPCv2::CreateGeometry()
  78 {
  79   //
  80   // Create the geometry of Time Projection Chamber version 2
  81   //
  82   //Begin_Html
  83   /*
  84     <img src="picts/AliTPC.gif">
  85   */
  86   //End_Html
  87   //Begin_Html
  88   /*
  89     <img src="picts/AliTPCv2Tree.gif">
  90   */
  91   //End_Html
  92
  93   //----------------------------------------------------------
  94   // This geometry is written using TGeo class
  95   // Firstly the shapes are defined, and only then the volumes
  96   // What is recognized by the MC are volumes
  97   //----------------------------------------------------------
  98   //
  99   //  tpc - this will be the mother volume
 100   //
 101
 102   //
 103   // here I define a volume TPC
 104   // retrive the medium name with "TPC_" as a leading string
 105   //
 106   TGeoPcon *tpc = new TGeoPcon(0.,360.,18); //18 sections
 107   tpc->DefineSection(0,-290.,77.,278.);
 108   tpc->DefineSection(1,-259.6,70.,278.);
 109   //
 110   tpc->DefineSection(2,-259.6,68.1,278.);
 111   tpc->DefineSection(3,-253.6,68.1,278.);
 112   //
 113   tpc->DefineSection(4,-253.6,68.,278.);
 114   tpc->DefineSection(5,-74.0,60.8,278.);
 115   //
 116   tpc->DefineSection(6,-74.0,60.1,278.);
 117   tpc->DefineSection(7,-73.3,60.1,278.);
 118   //
 119   tpc->DefineSection(8,-73.3,56.9,278.);
 120   tpc->DefineSection(9,73.3,56.9,278.);
 121   //
 122   tpc->DefineSection(10,73.3,60.1,278.);
 123   tpc->DefineSection(11,74.0,60.1,278.);
 124   //
 125   tpc->DefineSection(12,74.0,60.8,278.);
 126   tpc->DefineSection(13,253.6,65.5,278.);
 127   //
 128   tpc->DefineSection(14,253.6,65.6,278.);
 129   tpc->DefineSection(15,259.6,65.6,278.);
 130   //
 131   tpc->DefineSection(16,259.6,70.0,278.);
 132   tpc->DefineSection(17,290.,77.,278.);
 133   //
 134   TGeoMedium *m1 = gGeoManager->GetMedium("TPC_Air");
 135   TGeoVolume *v1 = new TGeoVolume("TPC_M",tpc,m1);
 136   //
 137   // drift volume - sensitive volume, extended beyond the
 138   // endcaps, because of the alignment
 139   //
 140   TGeoPcon *dvol = new TGeoPcon(0.,360.,6);
 141   dvol->DefineSection(0,-260.,74.5,264.4);
 142   dvol->DefineSection(1,-253.6,74.5,264.4);
 143   //
 144   dvol->DefineSection(2,-253.6,76.6774,258.);
 145   dvol->DefineSection(3,253.6,76.6774,258.);
 146   //
 147   dvol->DefineSection(4,253.6,74.5,264.4);
 148   dvol->DefineSection(5,260.,74.5,264.4);
 149   //
 150   TGeoMedium *m5 = gGeoManager->GetMedium("TPC_Ne-CO2-N-2");
 151   TGeoVolume *v9 = new TGeoVolume("TPC_Drift",dvol,m5);
 152   //
 153   v1->AddNode(v9,1);
 154   //
 155   // outer insulator
 156   //
 157   TGeoPcon *tpco = new TGeoPcon(0.,360.,6); //insulator
 158   //
 159   tpco->DefineSection(0,-256.6,264.8,278.);
 160   tpco->DefineSection(1,-253.6,264.8,278.);
 161   //
 162   tpco->DefineSection(2,-253.6,258.,278.);
 163   tpco->DefineSection(3,250.6,258.,278.);
 164   //
 165   tpco->DefineSection(4,250.6,258.,275.5);
 166   tpco->DefineSection(5,253.6,258.,275.5);
 167   //
 168   TGeoMedium *m2 = gGeoManager->GetMedium("TPC_CO2");
 169   TGeoVolume *v2 = new TGeoVolume("TPC_OI",tpco,m2);
 170   //
 171   // outer containment vessel
 172   //
 173   TGeoPcon *tocv = new TGeoPcon(0.,360.,6);  // containment vessel
 174   //
 175   tocv->DefineSection(0,-256.6,264.8,278.);
 176   tocv->DefineSection(1,-253.6,264.8,278.);
 177   //
 178   tocv->DefineSection(2,-253.6,274.8124,278.);
 179   tocv->DefineSection(3,247.6,274.8124,278.);
 180   //
 181   tocv->DefineSection(4,247.6,270.4,278.);
 182   tocv->DefineSection(5,250.6,270.4,278.);
 183   //
 184   TGeoMedium *m3 = gGeoManager->GetMedium("TPC_Al");
 185   TGeoVolume *v3 = new TGeoVolume("TPC_OCV",tocv,m3);
 186   //
 187   TGeoTube *to1 = new TGeoTube(274.8174,277.995,252.1); //epoxy
 188   TGeoTube *to2 = new TGeoTube(274.8274,277.985,252.1); //tedlar
 189   TGeoTube *to3 = new TGeoTube(274.8312,277.9812,252.1);//prepreg2
 190   TGeoTube *to4 = new TGeoTube(274.9062,277.9062,252.1);//nomex
 191   //
 192   TGeoMedium *sm1 = gGeoManager->GetMedium("TPC_Epoxy");
 193   TGeoMedium *sm2 = gGeoManager->GetMedium("TPC_Tedlar");
 194   TGeoMedium *sm3 = gGeoManager->GetMedium("TPC_Prepreg2");
 195   TGeoMedium *sm4 = gGeoManager->GetMedium("TPC_Nomex");
 196   //
 197   TGeoVolume *tov1 = new TGeoVolume("TPC_OCV1",to1,sm1);
 198   TGeoVolume *tov2 = new TGeoVolume("TPC_OCV2",to2,sm2);
 199   TGeoVolume *tov3 = new TGeoVolume("TPC_OCV3",to3,sm3);
 200   TGeoVolume *tov4 = new TGeoVolume("TPC_OCV4",to4,sm4);
 201  //-------------------------------------------------------
 202   //  Tpc Outer Field Cage
 203   //  daughters - composite (sandwich)
 204   //-------------------------------------------------------
 205
 206   TGeoPcon *tofc = new TGeoPcon(0.,360.,6);
 207   //
 208   tofc->DefineSection(0,-253.6,258.,269.6);
 209   tofc->DefineSection(1,-250.6,258.,269.6);
 210   //
 211   tofc->DefineSection(2,-250.6,258.,260.0676);
 212   tofc->DefineSection(3,250.6,258.,260.0676);
 213   //
 214   tofc->DefineSection(4,250.6,258.,275.5);
 215   tofc->DefineSection(5,253.6,258.,275.5);
 216   //
 217   TGeoVolume *v4 = new TGeoVolume("TPC_TOFC",tofc,m3);
 218   //sandwich
 219   TGeoTube *tf1 = new TGeoTube(258.0,260.0676,252.1); //tedlar
 220   TGeoTube *tf2 = new TGeoTube(258.0038,260.0638,252.1); //prepreg3
 221   TGeoTube *tf3 = new TGeoTube(258.0338,260.0338,252.1);//nomex
 222   //
 223   TGeoMedium *sm5 = gGeoManager->GetMedium("TPC_Prepreg3");
 224   //
 225   TGeoVolume *tf1v = new TGeoVolume("TPC_OFC1",tf1,sm2);
 226   TGeoVolume *tf2v = new TGeoVolume("TPC_OFC2",tf2,sm5);
 227   TGeoVolume *tf3v = new TGeoVolume("TPC_OFC3",tf3,sm4);
 228   //
 229   // outer part - positioning
 230   //
 231   tov1->AddNode(tov2,1); tov2->AddNode(tov3,1); tov3->AddNode(tov4,1);
 232   //
 233   tf1v->AddNode(tf2v,1); tf2v->AddNode(tf3v,1);
 234   //
 235   v3->AddNode(tov1,1,new TGeoTranslation(0.,0.,-1.5)); v4->AddNode(tf1v,1);
 236   //
 237   v2->AddNode(v3,1); v2->AddNode(v4,1);
 238   //
 239   v1->AddNode(v2,1);
 240   //--------------------------------------------------------------------
 241   // Tpc Inner INsulator (CO2)
 242   // the cones, the central drum and the inner f.c. sandwich with a piece
 243   // of the flane will be placed in the TPC
 244   //--------------------------------------------------------------------
 245   TGeoPcon *tpci = new TGeoPcon(0.,360.,4);
 246   //
 247   tpci->DefineSection(0,-253.6,68.4,76.6774);
 248   tpci->DefineSection(1,-74.0,61.2,76.6774);
 249   //
 250   tpci->DefineSection(2,74.0,61.2,76.6774);
 251   //
 252   tpci->DefineSection(3,253.6,65.9,76.6774);
 253   //
 254   TGeoVolume *v5 = new TGeoVolume("TPC_INI",tpci,m2);
 255   //
 256   // now the inner field cage - only part of flanges (2 copies)
 257   //
 258   TGeoTube *tif1 = new TGeoTube(69.9,76.6774,1.5);
 259   TGeoVolume *v6 = new TGeoVolume("TPC_IFC1",tif1,m3);
 260   //
 261  //---------------------------------------------------------
 262   // Tpc Inner Containment vessel - Muon side
 263   //---------------------------------------------------------
 264   TGeoPcon *tcms = new TGeoPcon(0.,360.,10);
 265   //
 266   tcms->DefineSection(0,-259.1,68.1,74.2);
 267   tcms->DefineSection(1,-253.6,68.1,74.2);
 268   //
 269   tcms->DefineSection(2,-253.6,68.1,68.4);
 270   tcms->DefineSection(3,-74.0,60.9,61.2);
 271   //
 272   tcms->DefineSection(4,-74.0,60.1,61.2);
 273   tcms->DefineSection(5,-73.3,60.1,61.2);
 274   //
 275   tcms->DefineSection(6,-73.3,56.9,61.2);
 276   tcms->DefineSection(7,-73.0,56.9,61.2);
 277   //
 278   tcms->DefineSection(8,-73.0,56.9,58.8);
 279   tcms->DefineSection(9,-71.3,56.9,58.8);
 280   //
 281   TGeoVolume *v7 = new TGeoVolume("TPC_ICVM",tcms,m3);
 282   //-----------------------------------------------
 283   // inner containment vessel - shaft side
 284   //-----------------------------------------------
 285   TGeoPcon *tcss = new TGeoPcon(0.,360.,10);
 286   //
 287   tcss->DefineSection(0,71.3,56.9,58.8);
 288   tcss->DefineSection(1,73.0,56.9,58.8);
 289   //
 290   tcss->DefineSection(2,73.0,56.9,61.2);
 291   tcss->DefineSection(3,73.3,56.9,61.2);
 292   //
 293   tcss->DefineSection(4,73.3,60.1,61.2);
 294   tcss->DefineSection(5,74.0,60.1,61.2);
 295   //
 296   tcss->DefineSection(6,74.0,60.9,61.2);
 297   tcss->DefineSection(7,253.6,65.6,65.9);
 298   //
 299   tcss->DefineSection(8,253.6,65.6,74.2);
 300   tcss->DefineSection(9,258.1,65.6,74.2);
 301   //
 302   TGeoVolume *v8 = new TGeoVolume("TPC_ICVS",tcss,m3);
 303   //-----------------------------------------------
 304   //  Inner field cage
 305   //  define 4 parts and make an assembly
 306   //-----------------------------------------------
 307   // part1 - Al - 2 copies
 308   TGeoTube *t1 = new TGeoTube(76.6774,78.845,0.75);
 309   TGeoVolume *tv1 = new TGeoVolume("TPC_IFC2",t1,m3);
 310   // sandwich - outermost parts - 2 copies
 311   TGeoTube *t2 = new TGeoTube(76.6774,78.845,74.175); // tedlar 38 microns
 312   TGeoTube *t3 = new TGeoTube(76.6812,78.8412,74.175); // prepreg2 500 microns
 313   TGeoTube *t4 = new TGeoTube(76.7312,78.7912,74.175); // prepreg3 300 microns
 314   TGeoTube *t5 = new TGeoTube(76.7612,78.7612,74.175); // nomex 2 cm
 315   //
 316   TGeoVolume *tv2 = new TGeoVolume("TPC_IFC3",t2,sm2);
 317   TGeoVolume *tv3 = new TGeoVolume("TPC_IFC4",t3,sm3);
 318   TGeoVolume *tv4 = new TGeoVolume("TPC_IFC5",t4,sm5);
 319   TGeoVolume *tv5 = new TGeoVolume("TPC_IFC6",t5,sm4);
 320   //
 321   // middle parts - 2 copies
 322   TGeoTube *t6 = new TGeoTube(76.6774,78.795,5.); // tedlar 38 microns
 323   TGeoTube *t7 = new TGeoTube(76.6812,78.7912,5.); // prepreg2 250 microns
 324   TGeoTube *t8 = new TGeoTube(76.7062,78.7662,5.); // prepreg3 300 microns
 325   TGeoTube *t9 = new TGeoTube(76.7362,78.7362,5.); // nomex 2 cm
 326   //
 327   TGeoVolume *tv6 = new TGeoVolume("TPC_IFC7",t6,sm2);
 328   TGeoVolume *tv7 = new TGeoVolume("TPC_IFC8",t7,sm3);
 329   TGeoVolume *tv8 = new TGeoVolume("TPC_IFC9",t8,sm5);
 330   TGeoVolume *tv9 = new TGeoVolume("TPC_IFC10",t9,sm4);
 331   // central part - 1 copy
 332   TGeoTube *t10 = new TGeoTube(76.6774,78.745,93.75); // tedlar 38 microns
 333   TGeoTube *t11 = new TGeoTube(76.6812,78.7412,93.75); // prepreg3 300 microns
 334   TGeoTube *t12 = new TGeoTube(76.7112,78.7112,93.75); // nomex 2 cm
 335   //
 336   TGeoVolume *tv10 = new TGeoVolume("TPC_IFC11",t10,sm2);
 337   TGeoVolume *tv11 = new TGeoVolume("TPC_IFC12",t11,sm5);
 338   TGeoVolume *tv12 = new TGeoVolume("TPC_IFC13",t12,sm4);
 339   //
 340   // inner part - positioning
 341   //
 342   // creating a sandwich
 343   tv2->AddNode(tv3,1); tv3->AddNode(tv4,1); tv4->AddNode(tv5,1);
 344   //
 345   tv6->AddNode(tv7,1); tv7->AddNode(tv8,1); tv8->AddNode(tv9,1);
 346   //
 347   tv10->AddNode(tv11,1); tv11->AddNode(tv12,1);
 348   //
 349   TGeoVolumeAssembly *tv100 = new TGeoVolumeAssembly("TPC_IFC");
 350   //
 351   tv100->AddNode(tv10,1);
 352   tv100->AddNode(tv6,1,new TGeoTranslation(0.,0.,-98.75));
 353   tv100->AddNode(tv6,2,new TGeoTranslation(0.,0.,98.75));
 354   tv100->AddNode(tv2,1,new TGeoTranslation(0.,0.,-177.925));
 355   tv100->AddNode(tv2,2,new TGeoTranslation(0.,0.,177.925));
 356   tv100->AddNode(tv1,1,new TGeoTranslation(0.,0.,-252.85));
 357   tv100->AddNode(tv1,2,new TGeoTranslation(0.,0.,252.85));
 358   //
 359   v5->AddNode(v6,1, new TGeoTranslation(0.,0.,-252.1));
 360   v5->AddNode(v6,2, new TGeoTranslation(0.,0.,252.1));
 361   v1->AddNode(v5,1); v1->AddNode(v7,1); v1->AddNode(v8,1);
 362   v9->AddNode(tv100,1);
 363   //
 364   // central drum
 365   //
 366   // flange + sandwich
 367   //
 368   TGeoPcon *cfl = new TGeoPcon(0.,360.,6);
 369   cfl->DefineSection(0,-71.1,59.7,61.2);
 370   cfl->DefineSection(1,-68.6,59.7,61.2);
 371   //
 372   cfl->DefineSection(2,-68.6,60.6324,61.2);
 373   cfl->DefineSection(3,68.6,60.6324,61.2);
 374   //
 375   cfl->DefineSection(4,68.6,59.7,61.2);
 376   cfl->DefineSection(5,71.1,59.7,61.2);
 377   //
 378   TGeoVolume *cflv = new TGeoVolume("TPC_CDR",cfl,m3);
 379   // sandwich
 380   TGeoTube *cd1 = new TGeoTube(60.6424,61.19,71.1);
 381   TGeoTube *cd2 = new TGeoTube(60.6462,61.1862,71.1);
 382   TGeoTube *cd3 = new TGeoTube(60.6662,61.1662,71.1);
 383   //
 384   TGeoMedium *sm6 = gGeoManager->GetMedium("TPC_Prepreg1");
 385   TGeoVolume *cd1v = new TGeoVolume("TPC_CDR1",cd1,sm2); //tedlar
 386   TGeoVolume *cd2v = new TGeoVolume("TPC_CDR2",cd2,sm6);// prepreg1
 387   TGeoVolume *cd3v = new TGeoVolume("TPC_CDR3",cd3,sm4); //nomex
 388   //
 389   // seals for central drum 2 copies
 390   //
 391   TGeoTube *cs = new TGeoTube(56.9,61.2,0.1);
 392   TGeoMedium *sm7 = gGeoManager->GetMedium("TPC_Mylar");
 393   TGeoVolume *csv = new TGeoVolume("TPC_CDRS",cs,sm7);
 394   v1->AddNode(csv,1,new TGeoTranslation(0.,0.,-71.));
 395   v1->AddNode(csv,2,new TGeoTranslation(0.,0.,71.));
 396   //
 397   // seal collars
 398   TGeoPcon *se = new TGeoPcon(0.,360.,6);
 399   se->DefineSection(0,-72.8,59.7,61.2);
 400   se->DefineSection(1,-72.3,59.7,61.2);
 401   //
 402   se->DefineSection(2,-72.3,58.85,61.2);
 403   se->DefineSection(3,-71.6,58.85,61.2);
 404   //
 405   se->DefineSection(4,-71.6,59.7,61.2);
 406   se->DefineSection(5,-71.3,59.7,61.2);
 407   //
 408   TGeoVolume *sev = new TGeoVolume("TPC_CDCE",se,m3);
 409   //
 410   TGeoTube *si = new TGeoTube(56.9,58.8,1.);
 411   TGeoVolume *siv = new TGeoVolume("TPC_CDCI",si,m3);
 412   //
 413   // define reflection matrix
 414   //
 415   TGeoRotation *ref = new TGeoRotation("ref",90.,0.,90.,270.,180.,0.);
 416   //
 417   cd1v->AddNode(cd2v,1); cd2v->AddNode(cd3v,1); cflv->AddNode(cd1v,1);
 418   //
 419   v1->AddNode(siv,1,new TGeoTranslation(0.,0.,-70.1));
 420   v1->AddNode(siv,2,new TGeoTranslation(0.,0.,70.1));
 421   v1->AddNode(sev,1); v1->AddNode(sev,2,ref); v1->AddNode(cflv,1);
 422   //
 423   // central membrane - 2 rings and a mylar membrane - assembly
 424   //
 425   TGeoTube *ih = new TGeoTube(81.05,84.05,0.3);
 426   TGeoTube *oh = new TGeoTube(250.,256.,.5);
 427   TGeoTube *mem = new TGeoTube(84.05,250,0.01);
 428   TGeoVolume *ihv = new TGeoVolume("TPC_IHVH",ih,m3);
 429   TGeoVolume *ohv = new TGeoVolume("TPC_OHVH",oh,m3);
 430   TGeoVolume *memv = new TGeoVolume("TPC_HV",mem,sm7);
 431   //
 432   TGeoVolumeAssembly *cm = new TGeoVolumeAssembly("TPC_HVMEM");
 433   cm->AddNode(ihv,1);
 434   cm->AddNode(ohv,1);
 435   cm->AddNode(memv,1);
 436   v9->AddNode(cm,1);
 437   //
 438   // end caps - they are make as an assembly of single segments
 439   // containing both readout chambers
 440   //
 441   Double_t OpeningAngle = 10.*TMath::DegToRad();
 442   Double_t thick=1.5; // rib
 443   Double_t shift = thick/TMath::Sin(OpeningAngle);
 444   //
 445   Double_t LowEdge = 86.3; // hole in the wheel
 446   Double_t UpEdge = 240.4; // hole in the wheel
 447   //
 448   new TGeoTubeSeg("sec",74.5,264.4,3.,0.,20.);
 449   //
 450   TGeoPgon *hole = new TGeoPgon("hole",0.,20.,1,4);
 451   //
 452   hole->DefineSection(0,-3.5,LowEdge-shift,UpEdge-shift);
 453   hole->DefineSection(1,-1.5,LowEdge-shift,UpEdge-shift);
 454   //
 455   hole->DefineSection(2,-1.5,LowEdge-shift,UpEdge+3.-shift);
 456   hole->DefineSection(3,3.5,LowEdge-shift,UpEdge+3.-shift);
 457   //
 458   Double_t ys = shift*TMath::Sin(OpeningAngle);
 459   Double_t xs = shift*TMath::Cos(OpeningAngle);
 460   TGeoTranslation *tr = new TGeoTranslation("tr",xs,ys,0.);
 461   tr->RegisterYourself();
 462   TGeoCompositeShape *chamber = new TGeoCompositeShape("sec-hole:tr");
 463   TGeoVolume *sv = new TGeoVolume("TPC_WSEG",chamber,m3);
 464   TGeoPgon *bar = new TGeoPgon("bar",0.,20.,1,2);
 465   bar->DefineSection(0,-3.,131.5-shift,136.5-shift);
 466   bar->DefineSection(1,1.5,131.5-shift,136.5-shift);
 467   TGeoVolume *barv = new TGeoVolume("TPC_WBAR",bar,m3);
 468   TGeoVolumeAssembly *ch = new TGeoVolumeAssembly("TPC_WCH");//empty segment
 469   //
 470   ch->AddNode(sv,1); ch->AddNode(barv,1,tr);
 471   //
 472   // readout chambers
 473   //
 474   // IROC first
 475   //
 476    TGeoTrd1 *ibody = new TGeoTrd1(13.8742,21.3328,4.29,21.15);
 477    TGeoVolume *ibdv = new TGeoVolume("TPC_IROCB",ibody,m3);
 478   // empty space
 479    TGeoTrd1 *emp = new TGeoTrd1(12.3742,19.8328,3.99,19.65);
 480    TGeoVolume *empv = new TGeoVolume("TPC_IROCE",emp,m1);
 481    ibdv->AddNode(empv,1,new TGeoTranslation(0.,-0.3,0.));
 482    //bars
 483    Double_t tga = (19.8328-12.3742)/39.3;
 484    Double_t xmin,xmax;
 485    xmin = 9.55*tga+12.3742;
 486    xmax = 9.95*tga+12.3742;
 487    TGeoTrd1 *ib1 = new TGeoTrd1(xmin,xmax,3.29,0.2);
 488    TGeoVolume *ib1v = new TGeoVolume("TPC_IRB1",ib1,m3);
 489    empv->AddNode(ib1v,1,new TGeoTranslation("tt1",0.,0.7,-9.9));
 490    xmin=19.4*tga+12.3742;
 491    xmax=19.9*tga+12.3742;
 492    TGeoTrd1 *ib2 = new TGeoTrd1(xmin,xmax,3.29,0.25);
 493    TGeoVolume *ib2v = new TGeoVolume("TPC_TRB2",ib2,m3);
 494    empv->AddNode(ib2v,1,new TGeoTranslation(0.,0.7,0.));
 495    xmin=29.35*tga+12.3742;
 496    xmax=29.75*tga+12.3742;
 497    TGeoTrd1 *ib3 = new TGeoTrd1(xmin,xmax,3.29,0.2);
 498    TGeoVolume *ib3v = new TGeoVolume("TPC_IRB3",ib3,m3);
 499    empv->AddNode(ib3v,1,new TGeoTranslation(0.,0.7,9.9));
 500    //
 501    // holes for connectors
 502    //
 503    TGeoBBox *conn = new TGeoBBox(0.4,0.3,4.675); // identical for iroc and oroc
 504    TGeoVolume *connv = new TGeoVolume("TPC_RCCON",conn,m1);
 505    TString fileName(gSystem->Getenv("ALICE_ROOT"));
 506    fileName += "/TPC/conn_iroc.dat";
 507    ifstream in;
 508    in.open(fileName.Data(), ios_base::in); // asci file
 509    for(Int_t i =0;i<86;i++){
 510       Double_t y = 3.99;
 511       Double_t x,z,ang;
 512       in>>x>>z>>ang;
 513       z-=26.5;
 514       TGeoRotation *rrr = new TGeoRotation();
 515       rrr->RotateY(ang);
 516       TGeoCombiTrans *trans = new TGeoCombiTrans("trans",x,y,z,rrr);
 517       ibdv->AddNode(connv,i+1,trans);
 518    }
 519    in.close();
 520    // "cap"
 521    new TGeoTrd1("icap",14.5974,23.3521,1.19,24.825);
 522    // "hole"
 523    new TGeoTrd1("ihole",13.8742,21.3328,1.2,21.15);
 524    TGeoTranslation *tr1 = new TGeoTranslation("tr1",0.,0.,1.725);
 525    tr1->RegisterYourself();
 526    TGeoCompositeShape *ic = new TGeoCompositeShape("icap-ihole:tr1");
 527    TGeoVolume *icv = new TGeoVolume("TPC_IRCAP",ic,m3);
 528    //
 529    // pad plane and wire fixations
 530    //
 531    TGeoTrd1 *pp = new TGeoTrd1(14.5974,23.3521,0.3,24.825); //pad+iso
 532    TGeoMedium *m4 = gGeoManager->GetMedium("TPC_G10");
 533    TGeoVolume *ppv = new TGeoVolume("TPC_IRPP",pp,m4);
 534    TGeoPara *f1 = new TGeoPara(.6,.5,24.825,0.,-10.,0.);
 535    TGeoVolume *f1v = new TGeoVolume("TPC_IRF1",f1,m4);
 536    TGeoPara *f2 = new TGeoPara(.6,.5,24.825,0.,10.,0.);
 537    TGeoVolume *f2v = new TGeoVolume("TPC_IRF2",f2,m4);
 538    //
 539    TGeoVolumeAssembly *iroc = new TGeoVolumeAssembly("TPC_IROC");
 540    //
 541    iroc->AddNode(ibdv,1);
 542    iroc->AddNode(icv,1,new TGeoTranslation(0.,3.1,-1.725));
 543    iroc->AddNode(ppv,1,new TGeoTranslation(0.,4.59,-1.725));
 544    tga =(23.3521-14.5974)/49.65;
 545    Double_t xx = 24.825*tga+14.5974-0.6;
 546    iroc->AddNode(f1v,1,new TGeoTranslation(-xx,5.39,-1.725));
 547    iroc->AddNode(f2v,1,new TGeoTranslation(xx,5.39,-1.725));
 548    //
 549    // OROC
 550    //
 551    TGeoTrd1 *obody = new TGeoTrd1(22.2938,40.5084,4.19,51.65);
 552    TGeoVolume *obdv = new TGeoVolume("TPC_OROCB",obody,m3);
 553    TGeoTrd1 *oemp = new TGeoTrd1(20.2938,38.5084,3.89,49.65);
 554    TGeoVolume *oempv = new TGeoVolume("TPC_OROCE",oemp,m1);
 555    obdv->AddNode(oempv,1,new TGeoTranslation(0.,-0.3,0.));
 556    //horizontal bars
 557    tga=(38.5084-20.2938)/99.3;
 558    xmin=tga*10.2+20.2938;
 559    xmax=tga*10.6+20.2938;
 560    TGeoTrd1 *ob1 = new TGeoTrd1(xmin,xmax,2.915,0.2);
 561    TGeoVolume *ob1v = new TGeoVolume("TPC_ORB1",ob1,m3);
 562    //
 563    xmin=22.55*tga+20.2938;
 564    xmax=24.15*tga+20.2938;
 565    TGeoTrd1 *ob2 = new TGeoTrd1(xmin,xmax,2.915,0.8);
 566    TGeoVolume *ob2v = new TGeoVolume("TPC_ORB2",ob2,m3);
 567    //
 568    xmin=36.1*tga+20.2938;
 569    xmax=36.5*tga+20.2938;
 570    TGeoTrd1 *ob3 = new TGeoTrd1(xmin,xmax,2.915,0.2);
 571    TGeoVolume *ob3v = new TGeoVolume("TPC_ORB3",ob3,m3);
 572    //
 573    xmin=49.0*tga+20.2938;
 574    xmax=50.6*tga+20.2938;
 575    TGeoTrd1 *ob4 = new TGeoTrd1(xmin,xmax,2.915,0.8);
 576    TGeoVolume *ob4v = new TGeoVolume("TPC_ORB4",ob4,m3);
 577    //
 578    xmin=63.6*tga+20.2938;
 579    xmax=64.0*tga+20.2938;
 580    TGeoTrd1 *ob5 = new TGeoTrd1(xmin,xmax,2.915,0.2);
 581    TGeoVolume *ob5v = new TGeoVolume("TPC_ORB5",ob5,m3);
 582    //
 583    xmin=75.5*tga+20.2938;
 584    xmax=77.15*tga+20.2938;
 585    TGeoTrd1 *ob6 = new TGeoTrd1(xmin,xmax,2.915,0.8);
 586    TGeoVolume *ob6v = new TGeoVolume("TPC_ORB6",ob6,m3);
 587    //
 588    xmin=88.7*tga+20.2938;
 589    xmax=89.1*tga+20.2938;
 590    TGeoTrd1 *ob7 = new TGeoTrd1(xmin,xmax,2.915,0.2);
 591    TGeoVolume *ob7v = new TGeoVolume("TPC_ORB7",ob7,m3);
 592    //
 593    oempv->AddNode(ob1v,1,new TGeoTranslation(0.,0.975,-39.25));
 594    oempv->AddNode(ob2v,1,new TGeoTranslation(0.,0.975,-26.3));
 595    oempv->AddNode(ob3v,1,new TGeoTranslation(0.,0.975,-13.35));
 596    oempv->AddNode(ob4v,1,new TGeoTranslation(0.,0.975,0.15));
 597    oempv->AddNode(ob5v,1,new TGeoTranslation(0.,0.975,14.15));
 598    oempv->AddNode(ob6v,1,new TGeoTranslation(0.,0.975,26.7));
 599    oempv->AddNode(ob7v,1,new TGeoTranslation(0.,0.975,39.25));
 600    // vertical bars
 601    TGeoBBox *ob8 = new TGeoBBox(0.8,2.915,5.1);
 602    TGeoBBox *ob9 = new TGeoBBox(0.8,2.915,5.975);
 603    TGeoBBox *ob10 = new TGeoBBox(0.8,2.915,5.775);
 604    TGeoBBox *ob11 = new TGeoBBox(0.8,2.915,6.25);
 605    TGeoBBox *ob12 = new TGeoBBox(0.8,2.915,6.5);
 606    //
 607    TGeoVolume *ob8v = new TGeoVolume("TPC_ORB8",ob8,m3);
 608    TGeoVolume *ob9v = new TGeoVolume("TPC_ORB9",ob9,m3);
 609    TGeoVolume *ob10v = new TGeoVolume("TPC_ORB10",ob10,m3);
 610    TGeoVolume *ob11v = new TGeoVolume("TPC_ORB11",ob11,m3);
 611    TGeoVolume *ob12v = new TGeoVolume("TPC_ORB12",ob12,m3);
 612    //
 613    oempv->AddNode(ob8v,1,new TGeoTranslation(0.,0.975,-44.55));
 614    oempv->AddNode(ob8v,2,new TGeoTranslation(0.,0.975,44.55));
 615    oempv->AddNode(ob9v,1,new TGeoTranslation(0.,0.975,-33.075));
 616    oempv->AddNode(ob9v,2,new TGeoTranslation(0.,0.975,-19.525));
 617    oempv->AddNode(ob10v,1,new TGeoTranslation(0.,0.975,20.125));
 618    oempv->AddNode(ob10v,2,new TGeoTranslation(0.,0.975,33.275));
 619    oempv->AddNode(ob11v,1,new TGeoTranslation(0.,0.975,-6.9));
 620    oempv->AddNode(ob12v,1,new TGeoTranslation(0.,0.975,7.45));
 621    //
 622    // holes for connectors
 623    //
 624    fileName = gSystem->Getenv("ALICE_ROOT");
 625    fileName += "/TPC/conn_oroc.dat";
 626    in.open(fileName.Data(), ios_base::in); // asci file
 627    for(Int_t i =0;i<78;i++){
 628       Double_t y =3.89;
 629       Double_t x,z,ang;
 630       Double_t x1,z1,x2,z2;
 631       in>>x>>z>>ang;
 632       Double_t xr = 4.7*TMath::Sin(ang*TMath::DegToRad());
 633       Double_t zr = 4.7*TMath::Cos(ang*TMath::DegToRad());
 634       //
 635       x1=xr+x; x2=-xr+x; z1=zr+z; z2 = -zr+z;
 636       //
 637       TGeoRotation *rr = new TGeoRotation();
 638       rr->RotateY(ang);
 639       z1-=54.95;
 640       z2-=54.95;
 641       TGeoCombiTrans *trans1 = new TGeoCombiTrans("trans1",x1,y,z1,rr);
 642       TGeoCombiTrans *trans2 = new TGeoCombiTrans("trans2",x2,y,z2,rr);
 643       obdv->AddNode(connv,i+1,trans1);
 644       obdv->AddNode(connv,i+79,trans2);
 645    }
 646    in.close();
 647    // cap
 648    new TGeoTrd1("ocap",23.3874,43.5239,1.09,57.1);
 649    new TGeoTrd1("ohole",22.2938,40.5084,1.09,51.65);
 650    TGeoTranslation *tr5 = new TGeoTranslation("tr5",0.,0.,-2.15);
 651    tr5->RegisterYourself();
 652    TGeoCompositeShape *oc = new TGeoCompositeShape("ocap-ohole:tr5");
 653    TGeoVolume *ocv = new TGeoVolume("TPC_ORCAP",oc,m3);
 654    //
 655    // pad plane and wire fixations
 656    //
 657    TGeoTrd1 *opp = new TGeoTrd1(23.3874,43.5239,0.3,57.1);
 658    TGeoVolume *oppv = new TGeoVolume("TPC_ORPP",opp,m4);
 659    //
 660    tga=(43.5239-23.3874)/114.2;
 661    TGeoPara *f3 = new TGeoPara(.7,.6,57.1,0.,-10.,0.);
 662    TGeoPara *f4 = new TGeoPara(.7,.6,57.1,0.,10.,0.);
 663    xx = 57.1*tga+23.3874-0.7;
 664    TGeoVolume *f3v = new TGeoVolume("TPC_ORF1",f3,m4);
 665    TGeoVolume *f4v = new TGeoVolume("TPC_ORF2",f4,m4);
 666    //
 667    TGeoVolumeAssembly *oroc = new TGeoVolumeAssembly("TPC_OROC");
 668    //
 669    oroc->AddNode(obdv,1);
 670    oroc->AddNode(ocv,1,new TGeoTranslation(0.,3.1,2.15));
 671    oroc->AddNode(oppv,1,new TGeoTranslation(0.,4.49,2.15));
 672    oroc->AddNode(f3v,1,new TGeoTranslation(-xx,5.39,2.15));
 673    oroc->AddNode(f4v,1,new TGeoTranslation(xx,5.39,2.15));
 674    //
 675    // now iroc and oroc are placed into a sector...
 676    //
 677    TGeoVolumeAssembly *sect = new TGeoVolumeAssembly("TPC_SECT");
 678    TGeoRotation rot1("rot1",90.,90.,0.);
 679    TGeoRotation rot2("rot2");
 680    rot2.RotateY(10.);
 681    TGeoRotation *rot = new TGeoRotation("rot");
 682    *rot=rot1*rot2;
 683    //
 684    Double_t x0,y0;
 685    x0=110.2*TMath::Cos(OpeningAngle);
 686    y0=110.2*TMath::Sin(OpeningAngle);
 687    TGeoCombiTrans *combi1 = new TGeoCombiTrans("combi1",x0,y0,1.09,rot);
 688    x0=188.45*TMath::Cos(OpeningAngle);
 689    y0=188.45*TMath::Sin(OpeningAngle);
 690    TGeoCombiTrans *combi2 = new TGeoCombiTrans("combi2",x0,y0,0.99,rot);
 691    //
 692    sect->AddNode(ch,1);
 693    sect->AddNode(iroc,1,combi1);
 694    sect->AddNode(oroc,1,combi2);
 695    //
 696    // segment is ready...
 697    // now I try to make a wheel...
 698    //
 699    TGeoVolumeAssembly *wheel = new TGeoVolumeAssembly("TPC_ENDCAP");
 700    //
 701    for(Int_t i =0;i<18;i++){
 702      Double_t phi = (20.*i);
 703      TGeoRotation *r = new TGeoRotation();
 704      r->RotateZ(phi);
 705      wheel->AddNode(sect,i+1,r);
 706
 707    }
 708    // wheels in the drift volume!
 709    v9->AddNode(wheel,1,new TGeoTranslation(0.,0.,-256.6));
 710    TGeoCombiTrans *combi3 = new TGeoCombiTrans("combi3",0.,0.,256.6,ref);
 711    v9->AddNode(wheel,2,combi3);
 712
 713    //_____________________________________________________________
 714    // service support wheel
 715    //_____________________________________________________________
 716   TGeoPgon *sw = new TGeoPgon(0.,20.,1,2);
 717   sw->DefineSection(0,-4.,80.5,251.75);
 718   sw->DefineSection(1,4.,80.5,251.75);
 719   TGeoVolume *swv = new TGeoVolume("TPC_SWSEG",sw,m3); //Al
 720   //
 721   thick=1.;
 722   shift = thick/TMath::Sin(OpeningAngle);
 723   TGeoPgon *sh = new TGeoPgon(0.,20.,1,2);
 724   sh->DefineSection(0,-4.,81.5-shift,250.75-shift);
 725   sh->DefineSection(1,4.,81.5-shift,250.75-shift);
 726   TGeoVolume *shv = new TGeoVolume("TPC_SWS1",sh,m1); //Air
 727   //
 728   TGeoMedium *m9 =  gGeoManager->GetMedium("TPC_Si");
 729   TGeoPgon *el = new TGeoPgon(0.,20.,1,2);
 730   el->DefineSection(0,-1.872,81.5-shift,250.75-shift);
 731   el->DefineSection(1,1.872,81.5-shift,250.75-shift);
 732   TGeoVolume *elv = new TGeoVolume("TPC_ELEC",el,m9); //Si
 733   //
 734   shv->AddNode(elv,1);
 735   //
 736   //
 737   ys = shift*TMath::Sin(OpeningAngle);
 738   xs = shift*TMath::Cos(OpeningAngle);
 739   swv->AddNode(shv,1,new TGeoTranslation(xs,ys,0.));
 740   // cover
 741   TGeoPgon *co = new TGeoPgon(0.,20.,1,2);
 742   co->DefineSection(0,-0.5,77.,255.25);
 743   co->DefineSection(1,0.5,77.,255.25);
 744   TGeoVolume *cov = new TGeoVolume("TPC_SWC1",co,m3);//Al
 745   // hole in a cover
 746   TGeoPgon *coh = new TGeoPgon(0.,20.,1,2);
 747   shift=4./TMath::Sin(OpeningAngle);
 748   coh->DefineSection(0,-0.5,85.-shift,247.25-shift);
 749   coh->DefineSection(1,0.5,85.-shift,247.25-shift);
 750   //
 751   TGeoVolume *cohv = new TGeoVolume("TPC_SWC2",coh,m1);
 752   //
 753   ys = shift*TMath::Sin(OpeningAngle);
 754   xs = shift*TMath::Cos(OpeningAngle);
 755   cov->AddNode(cohv,1,new TGeoTranslation(xs,ys,0.));
 756   //
 757   // Sector as an Assembly
 758   //
 759   TGeoVolumeAssembly *swhs = new TGeoVolumeAssembly("TPC_SSWSEC");
 760   swhs->AddNode(swv,1);
 761   swhs->AddNode(cov,1,new TGeoTranslation(0.,0.,-4.5));
 762   swhs->AddNode(cov,2,new TGeoTranslation(0.,0.,4.5));
 763   //
 764   // SSW as an Assembly of sectors
 765   //
 766  TGeoVolumeAssembly *swheel = new TGeoVolumeAssembly("TPC_SSWHEEL");
 767    for(Int_t i =0;i<18;i++){
 768      Double_t phi = (20.*i);
 769      TGeoRotation *r = new TGeoRotation();
 770      r->RotateZ(phi);
 771      swheel->AddNode(swhs,i+1,r);
 772    }
 773    v1->AddNode(swheel,1,new TGeoTranslation(0.,0.,-284.6));
 774    v1->AddNode(swheel,2,new TGeoTranslation(0.,0.,284.6));
 775
 776    // sensitive strips - strip "0" is always set
 777    // conditional
 778    Int_t totrows;
 779    totrows = fTPCParam->GetNRowLow() + fTPCParam->GetNRowUp();
 780    Double_t *upar;
 781    upar=NULL;
 782    gGeoManager->Volume("TPC_Strip","PGON",m5->GetId(),upar);
 783    upar=new Double_t [10];
 784    upar[0]=0.;
 785    upar[1]=360.;
 786    upar[2]=18.;
 787    upar[3]=2.;
 788    //
 789    upar[4]=-124.8;
 790    upar[7]=124.8;
 791
 792    Double_t rlow=fTPCParam->GetPadRowRadiiLow(0);
 793
 794    upar[5]=rlow;
 795    upar[6]=rlow+.01;
 796    upar[8]=upar[5];
 797    upar[9]=upar[6];
 798    //
 799    gGeoManager->Node("TPC_Strip",1,"TPC_Drift",0.,0.,124.82,0,kTRUE,upar,10);
 800    gGeoManager->Node("TPC_Strip",totrows+1,
 801                      "TPC_Drift",0.,0.,-124.82,0,kTRUE,upar,10);
 802    //
 803    // now, strips optionally
 804    //
 805    if(fSens){
 806      //lower sectors
 807      for(Int_t i=2;i<fTPCParam->GetNRowLow()+1;i++){
 808        rlow=fTPCParam->GetPadRowRadiiLow(i-1);
 809        upar[5]=rlow;
 810        upar[6]=rlow+.01;
 811        upar[8]=upar[5];
 812        upar[9]=upar[6];
 813        gGeoManager->Node("TPC_Strip",i,
 814                          "TPC_Drift",0.,0.,124.82,0,kTRUE,upar,10);
 815        gGeoManager->Node("TPC_Strip",totrows+i,
 816                          "TPC_Drift",0.,0.,-124.82,0,kTRUE,upar,10);
 817      }
 818      //upper sectors
 819      for(Int_t i=1;i<fTPCParam->GetNRowUp()+1;i++){
 820        rlow=fTPCParam->GetPadRowRadiiUp(i-1);
 821        upar[5]=rlow;
 822        upar[6]=rlow+.01;
 823        upar[8]=upar[5];
 824        upar[9]=upar[6];
 825        gGeoManager->Node("TPC_Strip",i+fTPCParam->GetNRowLow(),
 826                          "TPC_Drift",0.,0.,124.82,0,kTRUE,upar,10);
 827        gGeoManager->Node("TPC_Strip",totrows+i+fTPCParam->GetNRowLow(),
 828                          "TPC_Drift",0.,0.,-124.82,0,kTRUE,upar,10);
 829      }
 830    }//strips
 831   //----------------------------------------------------------
 832   // TPc Support Rods - MAKROLON
 833   //----------------------------------------------------------
 834   TGeoMedium *m6=gGeoManager->GetMedium("TPC_Makrolon");
 835   TGeoMedium *m7=gGeoManager->GetMedium("TPC_Cu");
 836   // upper and lower rods differ in length!
 837   delete [] upar;
 838   upar=NULL;
 839   gGeoManager->Volume("TPC_Rod","TUBE",m6->GetId(),upar);
 840   upar=new Double_t [3];
 841   upar[0]=1.8;
 842   upar[1]=2.2;
 843
 844   //
 845   //HV rods - makrolon + 0.58cm (diameter) Cu
 846   TGeoTube *hvr = new TGeoTube(0.,2.2,126.64);
 847   TGeoTube *hvc = new TGeoTube(0.,0.29,126.64);
 848   //
 849   TGeoVolume *hvrv = new TGeoVolume("TPC_HV_Rod",hvr,m6);
 850   TGeoVolume *hvcv = new TGeoVolume("TPC_HV_Cable",hvc,m7);
 851   hvrv->AddNode(hvcv,1);
 852
 853   for(Int_t i=0;i<18;i++){
 854     Double_t angle,x,y;
 855     Double_t z,r;
 856     angle=TMath::DegToRad()*20.*(Double_t)i;
 857     r=81.5;
 858     x=r * TMath::Cos(angle);
 859     y=r * TMath::Sin(angle);
 860     upar[2]=126.64; //lower
 861     z= 126.96;
 862     if(i==15){
 863       v9->AddNode(hvrv,1,new TGeoTranslation(x,y,z));
 864       v9->AddNode(hvrv,2,new TGeoTranslation(x,y,-z));
 865     }
 866     else{
 867      gGeoManager->Node("TPC_Rod",i+1,"TPC_Drift",x,y,z,0,kTRUE,upar,3);//shaft
 868      gGeoManager->Node("TPC_Rod",i+18,"TPC_Drift",x,y,-z,0,kTRUE,upar,3);//muon
 869     }
 870     r=254.25;
 871     x=r * TMath::Cos(angle);
 872     y=r * TMath::Sin(angle);
 873     upar[2]=126.54; //upper
 874     z=127.06;
 875     gGeoManager->Node("TPC_Rod",i+36,"TPC_Drift",x,y,z,0,kTRUE,upar,3);
 876     gGeoManager->Node("TPC_Rod",i+54,"TPC_Drift",x,y,-z,0,kTRUE,upar,3);
 877   }
 878
 879   TGeoVolume *alice = gGeoManager->GetVolume("ALIC");
 880   alice->AddNode(v1,1);
 881
 882
 883 } // end of function
 884
 885 //_____________________________________________________________________________
 886 void AliTPCv2::DrawDetector()
 887 {
 888   //
 889   // Draw a shaded view of the Time Projection Chamber version 1
 890   //
 891
 892   // Set everything unseen
 893   gMC->Gsatt("*", "seen", -1);
 894   //
 895   // Set ALIC mother transparent
 896   gMC->Gsatt("ALIC","SEEN",0);
 897   //
 898   // Set the volumes visible
 899   //
 900
 901   gMC->Gsatt("TPC ","SEEN",0);
 902   gMC->Gsatt("TOIN","SEEN",1);
 903   gMC->Gsatt("TOIN","COLO",7);
 904   gMC->Gsatt("TOCV","SEEN",1);
 905   gMC->Gsatt("TOCV","COLO",4);
 906   gMC->Gsatt("TSA1","SEEN",0);
 907   gMC->Gsatt("TSA2","SEEN",0);
 908   gMC->Gsatt("TSA3","SEEN",0);
 909   gMC->Gsatt("TSA4","SEEN",0);
 910   gMC->Gsatt("TSA5","SEEN",0);
 911   gMC->Gsatt("TOFC","SEEN",1);
 912   gMC->Gsatt("TOFC","COLO",4);
 913   gMC->Gsatt("TSA6","SEEN",0);
 914   gMC->Gsatt("TSA7","SEEN",0);
 915   gMC->Gsatt("TSA8","SEEN",0);
 916   gMC->Gsatt("TIIN","SEEN",1);
 917   gMC->Gsatt("TIIN","COLO",7);
 918   gMC->Gsatt("TII1","SEEN",0);
 919   gMC->Gsatt("TIFC","SEEN",1);
 920   gMC->Gsatt("TIFC","COLO",4);
 921   gMC->Gsatt("TSA9","SEEN",0);
 922   gMC->Gsatt("TS10","SEEN",0);
 923   gMC->Gsatt("TS11","SEEN",0);
 924   gMC->Gsatt("TS12","SEEN",0);
 925   gMC->Gsatt("TS13","SEEN",0);
 926   gMC->Gsatt("TS14","SEEN",0);
 927   gMC->Gsatt("TICC","SEEN",0);
 928   gMC->Gsatt("TICM","SEEN",0);
 929   gMC->Gsatt("TS15","SEEN",0);
 930   gMC->Gsatt("TS16","SEEN",0);
 931   gMC->Gsatt("TS17","SEEN",0);
 932   gMC->Gsatt("TS18","SEEN",0);
 933   gMC->Gsatt("TS19","SEEN",0);
 934   gMC->Gsatt("TPJ1","SEEN",0);
 935   gMC->Gsatt("TPJ2","SEEN",0);
 936   gMC->Gsatt("TICS","SEEN",0);
 937   gMC->Gsatt("TDGN","SEEN",0);
 938   gMC->Gsatt("TIRC","SEEN",0);
 939   gMC->Gsatt("TIC1","SEEN",1);
 940   gMC->Gsatt("TIPP","SEEN",0);
 941   gMC->Gsatt("TIC3","SEEN",0);
 942   gMC->Gsatt("TRCE","SEEN",0);
 943   gMC->Gsatt("TPSC","SEEN",0);
 944   gMC->Gsatt("TPCC","SEEN",0);
 945   gMC->Gsatt("TORC","SEEN",0);
 946   gMC->Gsatt("TOPP","SEEN",0);
 947   gMC->Gsatt("TOC3","SEEN",0);
 948   gMC->Gsatt("TOC1","SEEN",1);
 949   gMC->Gsatt("TSSW","SEEN",1);
 950   gMC->Gsatt("TSWC","SEEN",1);
 951   gMC->Gsatt("TSSW","COLO",3);
 952   gMC->Gsatt("TSWC","COLO",3);
 953   gMC->Gsatt("TSCE","COLO",6);
 954   gMC->Gsatt("TSCE","SEEN",1);
 955   gMC->Gsatt("TWES","SEEN",0);
 956   gMC->Gsatt("TSWB","SEEN",0);
 957   gMC->Gsatt("TPEL","SEEN",0);
 958   gMC->Gsatt("TPMW","SEEN",1);
 959   gMC->Gsatt("TESR","SEEN",1);
 960   gMC->Gsatt("TPMW","COLO",12);
 961   gMC->Gsatt("TIC1","COLO",5);
 962   gMC->Gsatt("TOC1","COLO",5);
 963   gMC->Gsatt("TESB","SEEN",0);
 964   gMC->Gsatt("THVM","SEEN",1);
 965   gMC->Gsatt("THVM","COLO",11);
 966   gMC->Gsatt("THVH","SEEN",0);
 967   gMC->Gsatt("TPSR","SEEN",0);
 968   gMC->Gsatt("THVL","SEEN",0);
 969   gMC->Gsatt("THVC","SEEN",0);
 970   gMC->Gsatt("THVE","SEEN",0);
 971   gMC->Gsatt("THVR","SEEN",0);
 972   gMC->Gsatt("TPSS","SEEN",0);
 973   gMC->Gsatt("TPUS","SEEN",0);
 974   gMC->Gsatt("TPLS","SEEN",0);
 975
 976   //
 977   gMC->Gdopt("hide", "on");
 978   gMC->Gdopt("shad", "on");
 979   gMC->Gsatt("*", "fill", 7);
 980   gMC->SetClipBox(".");
 981   gMC->SetClipBox("TPMW",-300,300,-300,300,254.,270.);
 982   gMC->SetClipBox("TESR",-300,300,-300,300,254.,270.);
 983   gMC->SetClipBox("TSSW",-300,300,-300,300,283.,284.);
 984   gMC->SetClipBox("TSWC",-300,300,-300,300,283.,284.);
 985   gMC->SetClipBox("*", 0, 300, -300, 300, -290, 290);
 986   gMC->DefaultRange();
 987   gMC->Gdraw("alic", 40, 30, 0, 12, 9.5, .025, .025);
 988   gMC->Gdhead(1111, "Time Projection Chamber");
 989   gMC->Gdman(18, 4, "MAN");
 990   gMC->Gdopt("hide","off");
 991 }
 992
 993 //_____________________________________________________________________________
 994 void AliTPCv2::CreateMaterials()
 995 {
 996   //
 997   // Define materials for version 2 of the Time Projection Chamber
 998   //
 999
1000   AliTPC::CreateMaterials();
1001 }
1002
1003 //_____________________________________________________________________________
1004 void AliTPCv2::Init()
1005 {
1006   //
1007   // Initialises version 2 of the TPC after that it has been built
1008   //
1009
1010   Int_t *idtmed = fIdtmed->GetArray();
1011
1012   AliTPC::Init();
1013
1014
1015   fIdSens=gMC->VolId("TPC_Strip");  // one strip is always selected...
1016
1017   fIDrift=gMC->VolId("TPC_Drift");
1018   fSecOld=-100; // fake number
1019
1020   gMC->SetMaxNStep(30000); // max. number of steps increased
1021
1022   gMC->Gstpar(idtmed[2],"LOSS",5); // specific energy loss
1023
1024   AliInfo("*** TPC version 2 initialized ***");
1025   AliInfo(Form("Maximum number of steps = %d",gMC->GetMaxNStep()));
1026
1027   //
1028
1029 }
1030
1031 //_____________________________________________________________________________
1032 void AliTPCv2::StepManager()
1033 {
1034   //
1035   // Called for every step in the Time Projection Chamber
1036   //
1037
1038   //
1039   // parameters used for the energy loss calculations
1040   //
1041   const Float_t kprim = 14.35; // number of primary collisions per 1 cm
1042   const Float_t kpoti = 20.77e-9; // first ionization potential for Ne/CO2
1043   const Float_t kwIon = 35.97e-9; // energy for the ion-electron pair creation
1044
1045
1046   const Float_t kbig = 1.e10;
1047
1048   Int_t id,copy;
1049   Float_t hits[5];
1050   Int_t vol[2];
1051   TLorentzVector p;
1052
1053   vol[1]=0; // preset row number to 0
1054   //
1055   gMC->SetMaxStep(kbig);
1056
1057   if(!gMC->IsTrackAlive()) return; // particle has disappeared
1058
1059   Float_t charge = gMC->TrackCharge();
1060
1061   if(TMath::Abs(charge)<=0.) return; // take only charged particles
1062
1063   // check the sensitive volume
1064
1065   id = gMC->CurrentVolID(copy); // vol ID and copy number (starts from 1!)
1066   if(id != fIDrift && id != fIdSens) return; // not in the sensitive folume
1067
1068   gMC->TrackPosition(p);
1069   Double_t r = TMath::Sqrt(p[0]*p[0]+p[1]*p[1]);
1070   //
1071
1072   //
1073   Double_t angle = TMath::ACos(p[0]/r);
1074   angle = (p[1]<0.) ? TMath::TwoPi()-angle : angle;
1075   //
1076   // angular segment, it is not a real sector number...
1077   //
1078   Int_t sector=TMath::Nint((angle-fTPCParam->GetInnerAngleShift())/
1079                fTPCParam->GetInnerAngle());
1080   // rotate to segment "0"
1081   Float_t cos,sin;
1082   fTPCParam->AdjustCosSin(sector,cos,sin);
1083   Float_t x1=p[0]*cos + p[1]*sin;
1084   // check if within sector's limits
1085   if(x1>=fTPCParam->GetInnerRadiusLow()&&x1<=fTPCParam->GetInnerRadiusUp()
1086      ||x1>=fTPCParam->GetOuterRadiusLow()&&x1<=fTPCParam->GetOuterRadiusUp()){
1087   // calculate real sector number...
1088   if (x1>fTPCParam->GetOuterRadiusLow()){
1089     sector = TMath::Nint((angle-fTPCParam->GetOuterAngleShift())/
1090              fTPCParam->GetOuterAngle())+fTPCParam->GetNInnerSector();
1091     if (p[2]<0)         sector+=(fTPCParam->GetNOuterSector()>>1);
1092   }
1093     else
1094       if (p[2]<0) sector+=(fTPCParam->GetNInnerSector()>>1);
1095   //
1096   // here I have a sector number
1097   //
1098
1099   vol[0]=sector;
1100   // check if change of sector
1101   if(sector != fSecOld){
1102     fSecOld=sector;
1103     // add track reference
1104     AddTrackReference(gAlice->GetMCApp()->GetCurrentTrackNumber());
1105   }
1106   // track is in the sensitive strip
1107   if(id == fIdSens){
1108     // track is entering the strip
1109     if (gMC->IsTrackEntering()){
1110       Int_t totrows = fTPCParam->GetNRowLow()+fTPCParam->GetNRowUp();
1111       vol[1] = (copy<=totrows) ? copy-1 : copy-1-totrows;
1112       // row numbers are autonomous for lower and upper sectors
1113       if(vol[0] > fTPCParam->GetNInnerSector()) {
1114         vol[1] -= fTPCParam->GetNRowLow();
1115       }
1116     //
1117       if(vol[0]<fTPCParam->GetNInnerSector()&&vol[1] == 0){
1118
1119         // lower sector, row 0, because Jouri wants to have this
1120
1121         gMC->TrackMomentum(p);
1122         hits[0]=p[0];
1123         hits[1]=p[1];
1124         hits[2]=p[2];
1125         hits[3]=0.; // this hit has no energy loss
1126         // Get also the track time for pileup simulation
1127         hits[4]=gMC->TrackTime();
1128
1129         AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber(), vol,hits);
1130       }
1131     //
1132
1133        gMC->TrackPosition(p);
1134        hits[0]=p[0];
1135        hits[1]=p[1];
1136        hits[2]=p[2];
1137        hits[3]=0.; // this hit has no energy loss
1138        // Get also the track time for pileup simulation
1139        hits[4]=gMC->TrackTime();
1140
1141        AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber(), vol,hits);
1142
1143     }
1144     else return;
1145   }
1146   //-----------------------------------------------------------------
1147   //  charged particle is in the sensitive drift volume
1148   //-----------------------------------------------------------------
1149   if(gMC->TrackStep() > 0) {
1150
1151     Int_t nel = (Int_t)(((gMC->Edep())-kpoti)/kwIon) + 1;
1152     nel=TMath::Min(nel,300); // 300 electrons corresponds to 10 keV
1153     //
1154     gMC->TrackPosition(p);
1155     hits[0]=p[0];
1156     hits[1]=p[1];
1157     hits[2]=p[2];
1158     hits[3]=(Float_t)nel;
1159
1160     // Add this hit
1161
1162     if (fHitType&&2){
1163       gMC->TrackMomentum(p);
1164       Float_t momentum = TMath::Sqrt(p[0]*p[0]+p[1]*p[1]);
1165       Float_t precision =   (momentum>0.1) ? 0.002 :0.01;
1166       fTrackHits->SetHitPrecision(precision);
1167     }
1168
1169     // Get also the track time for pileup simulation
1170     hits[4]=gMC->TrackTime();
1171
1172     AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber(), vol,hits);
1173
1174   } // step>0
1175   } //within sector's limits
1176   // Stemax calculation for the next step
1177
1178   Float_t pp;
1179   TLorentzVector mom;
1180   gMC->TrackMomentum(mom);
1181   Float_t ptot=mom.Rho();
1182   Float_t betaGamma = ptot/gMC->TrackMass();
1183
1184   Int_t pid=gMC->TrackPid();
1185   if((pid==kElectron || pid==kPositron) && ptot > 0.002)
1186     {
1187       pp = kprim*1.58; // electrons above 20 MeV/c are on the plateau!
1188     }
1189   else
1190     {
1191
1192       betaGamma = TMath::Max(betaGamma,(Float_t)7.e-3); // protection against too small bg
1193       pp=kprim*BetheBloch(betaGamma);
1194
1195       if(TMath::Abs(charge) > 1.) pp *= (charge*charge);
1196     }
1197
1198   Double_t rnd = gMC->GetRandom()->Rndm();
1199
1200   gMC->SetMaxStep(-TMath::Log(rnd)/pp);
1201
1202
1203 }
1204
1205 //_____________________________________________________________________________
1206 Float_t AliTPCv2::BetheBloch(Float_t bg)
1207 {
1208   //
1209   // Bethe-Bloch energy loss formula
1210   //
1211   const Double_t kp1=0.76176e-1;
1212   const Double_t kp2=10.632;
1213   const Double_t kp3=0.13279e-4;
1214   const Double_t kp4=1.8631;
1215   const Double_t kp5=1.9479;
1216
1217   Double_t dbg = (Double_t) bg;
1218
1219   Double_t beta = dbg/TMath::Sqrt(1.+dbg*dbg);
1220
1221   Double_t aa = TMath::Power(beta,kp4);
1222   Double_t bb = TMath::Power(1./dbg,kp5);
1223
1224   bb=TMath::Log(kp3+bb);
1225
1226   return ((Float_t)((kp2-aa-bb)*kp1/aa));
1227 }
1228
1229