]> git.uio.no Git - u/mrichter/AliRoot.git/blobdiff - TPC/AliTPCv1.cxx
The changes w.r.t. the previous version:
[u/mrichter/AliRoot.git] / TPC / AliTPCv1.cxx
index 127c8f39a96c1501f1674427ef3c88009efc65a3..df337d8f46ecf7167197e690ad3b56022c1140a1 100644 (file)
@@ -57,449 +57,642 @@ void AliTPCv1::CreateGeometry()
   */
   //End_Html
 
-  AliMC* pMC = AliMC::GetMC();
-
-  Int_t *idtmed = gAlice->Idtmed();
+  AliTPCParam * fTPCParam = &(fDigParam->GetParam());
 
+  Int_t *idtmed = fIdtmed->GetArray();
 
-  AliTPCParam * fTPCParam = &(fDigParam->GetParam());
-  
-  Float_t tana, rlsl, wlsl, rssl, rlsu, wssl, wlsu,
-    rssu, wssu, alpha, x, y, z, sec_thick;
-  
-  Float_t r1, r2, x1, z0, z1, x2, theta1, theta2, theta3, dm[21];
-  Int_t il, iu;
-  Float_t z_side, zz;
+  Float_t dm[21];
   Int_t idrotm[100];
-  
-  Float_t x0l, x0u;
-  Int_t idr;
-  Float_t thl;
-  Int_t ils;
-  Float_t opl;
-  Int_t iss;
-  Float_t thu, opu, phi1, phi2, phi3;
-  
+
+  Int_t nRotMat = 0;
+
+
   // ---------------------------------------------------- 
-  //          FIELD CAGE WITH ENDCAPS - CARBON FIBER 
+  //          FIELD CAGE WITH ENDCAPS - G10
   //          THIS IS ALSO A TPC MOTHER VOLUME 
   // ---------------------------------------------------- 
+
   dm[0] = 76.;
   dm[1] = 278.;
   dm[2] = 275.;
-  
-  pMC->Gsvolu("TPC ", "TUBE", idtmed[407], dm, 3);
-  
-  // ------------------------------------------------------- 
-  //     drift gas Ne/CO2 (90/10 volume) - nonsensitive 
-  //     field cage thickness = 0.52% X0 
-  // ---------------------------------------------------- 
-  
-  //Begin_Html
-  /*
-    <img src="picts/spec_tgas1.gif">
-  */
-  //End_Html
-  
-  dm[0] = 76.+0.09776;
-  dm[1] = 257.;
+
+  gMC->Gsvolu("TPC ", "TUBE", idtmed[8], dm, 3); 
+
+  //-----------------------------------------------------
+  //  Endcap cover c-fibre 0.86% X0
+  //-----------------------------------------------------
+
+  dm[0] = 78.;
+  dm[1] = 258.;
+  dm[2] = 0.95;
+
+  gMC->Gsvolu("TPEC","TUBE",idtmed[10],dm,3);
+
+  //-----------------------------------------------------
+  // Drift gas , leave 2 cm at the outer radius
+  // and inner raddius
+  //-----------------------------------------------------
+
+  dm[0] = 78.;
+  dm[1] = 258.;
   dm[2] = 250.;
-  
-  pMC->Gsvolu("TGAS", "TUBE", idtmed[402], dm, 3);
-  
-  // ------------------------------------------------------ 
-  //     "side" gas volume (the same as drift gas), 
-  //      here the readout chambers are positioned 
-  // ------------------------------------------------------ 
-  
-  //Begin_Html
-  /*
-    <img src="picts/spec_tpsg1.gif">
-  */
-  //End_Html
-  
-  dm[2]  = 12.5;
-  z_side = dm[2];
-  
-  pMC->Gsvolu("TPSG", "TUBE", idtmed[401], dm, 3);
-  // ------------------------------------------------------ 
-  //      HV midplane - 20 microns of mylar 
-  // ----------------------------------------------------- 
-  dm[2] = .001;
-  
-  pMC->Gsvolu("TPHV", "TUBE", idtmed[405], dm, 3);
-  
-  // ==================================================== 
-  //   lower and upper readout chambers 
-  // ==================================================== 
-  //   sectors opening angles in degrees 
-  // --------------------------------------------------- 
-  opl = 30.;
-  opu = 15.;
-  thl = TMath::Tan(opl * .5 * kDegrad);
-  thu = TMath::Tan(opu * .5 * kDegrad);
-  // --------------------------------------------------- 
-  //         S and L-sectors radii 
-  // --------------------------------------------------- 
-  rssl = 88.;
-  rssu = 136.;
-  rlsl = 142.;
-  rlsu = 250.;
-  // -------------------------------------------------- 
-  //          Sectors widths 
-  // -------------------------------------------------- 
-  wssl = 46.5;
-  wssu = 72.2;
-  wlsl = 37.;
-  wlsu = 65.4;
-  // --------------------------------------------------- 
-  //    Sector thickness 25% of X0 (Al) 
-  // --------------------------------------------------- 
-  sec_thick = 2.225;
-  // --------------------------------------------------- 
-  //     S-sectors (lower sectors) 
-  // --------------------------------------------------- 
-  dm[0] = wssl * .5;
-  dm[1] = wssu * .5;
-  dm[2] = sec_thick * .5;
-  dm[3] = (rssu - rssl) * .5;
-  
-  x0l = rssl + dm[3];
-  
-  //Begin_Html
-  /*
-    <img src="picts/spec_trcs1.gif">
-  */
-  //End_Html
-  
-  
-  pMC->Gsvolu("TRCS", "TRD1", idtmed[399], dm, 4);
-  // ----------------------------------------------------- 
-  //     S-sectors --> "gas sectors" 
-  // ----------------------------------------------------- 
-  
-  //Begin_Html
-  /*
-    <img src="picts/spec_tsga1.gif">
-  */
-  //End_Html
 
-  dm[2] = (250.-0.001)/2.;
-  pMC->Gsvolu("TSGA", "TRD1", idtmed[402], dm, 4);
-  // --------------------------------------------------- 
-  //     L-sectors (upper sectors) 
-  // --------------------------------------------------- 
-  dm[0] = wlsl * .5;
-  dm[1] = wlsu * .5;
-  dm[2] = sec_thick * .5;
-  dm[3] = (rlsu - rlsl) * .5;
-  
-  x0u = rlsl + dm[3];
-
-  pMC->Gsvolu("TRCL", "TRD1", idtmed[399], dm, 4);
-  // ----------------------------------------------------- 
-  //     L-sectors - "gas sectors" 
-  // ----------------------------------------------------- 
-  dm[2] = (250.-0.001)/2.;
-  pMC->Gsvolu("TLGA", "TRD1", idtmed[402], dm, 4);
-  // ----------------------------------------------------- 
-  //  thin sensitive strips (100 microns) placed at a center 
-  //  of each pad row  in the "drift gas sector" 
-  // ----------------------------------------------------- 
-  pMC->Gsvolu("TSST", "TRD1", idtmed[403], dm, 0);
-  
-  dm[3] = .005;
-  z0    = rssl + (rssu - rssl) * .5;
+  gMC->Gsvolu("TGAS", "TUBE", idtmed[3], dm, 3);
+
+
+  //------------------------------------------------------
+  //  membrane holder - carbon fiber
+  //------------------------------------------------------
+
+
+  gMC->Gsvolu("TPMH","TUBE",idtmed[6],dm,0);
+
+  dm[0] = 252.;
+  dm[1] = 258.;
+  dm[2] = 0.2;
+
+  gMC->Gsposp("TPMH",1,"TGAS",0.,0.,0.,0,"ONLY",dm,3);
+  dm[0] = 78.;
+  dm[2] = 82.;
+  dm[2] = 0.1;
+
+  gMC->Gsposp("TPMH",2,"TGAS",0.,0.,0.,0,"ONLY",dm,3);
+
+  //----------------------------------------------------------
+  //  HV membrane - 25 microns of mylar
+  //----------------------------------------------------------
+
+  dm[0] = 82.;
+  dm[1] = 252.;
+  dm[2] = 0.00125;
+
+  gMC->Gsvolu("TPHV","TUBE",idtmed[5],dm,3);
+
+  gMC->Gspos("TPHV",1,"TGAS",0.,0.,0.,0,"ONLY");
+
+  gMC->Gspos("TGAS",1,"TPC ",0.,0.,0.,0,"ONLY");
+
+  //----------------------------------------------------------
+  // "side" gas volume, the same as the drift gas
+  // the readout chambers are placed there.  
+  //----------------------------------------------------------
+
+  dm[0] = 78.;
+  dm[1] = 258.;
+  dm[2] = 0.5*(275. - 250.);
+   
+  gMC->Gsvolu("TPSG", "TUBE", idtmed[2], dm, 3);
+
+  Float_t z_side = dm[2]; // 1/2 of the side gas thickness
+
+  //-----------------------------------------------------------
+  //   Readout chambers , 25% of X0, I use Al as the material
+  //-----------------------------------------------------------
+
+  Float_t InnerOpenAngle = fTPCParam->GetInnerAngle();
+  Float_t OuterOpenAngle = fTPCParam->GetOuterAngle();
+
+  Float_t InnerAngleShift = fTPCParam->GetInnerAngleShift();
+  Float_t OuterAngleShift = fTPCParam->GetOuterAngleShift();
+
+
+  Int_t nInnerSector = fTPCParam->GetNInnerSector()/2;
+  Int_t nOuterSector = fTPCParam->GetNOuterSector()/2;
+
+
+  Float_t InSecLowEdge = fTPCParam->GetInSecLowEdge();
+  Float_t InSecUpEdge =  fTPCParam->GetInSecUpEdge();
+
+  Float_t OuSecLowEdge = fTPCParam->GetOuSecLowEdge();
+  Float_t OuSecUpEdge = fTPCParam->GetOuSecUpEdge();
+
+  Float_t SecThick = 2.225; // Al
+
+  Float_t edge = fTPCParam->GetEdge();
+
+  //  S (Inner) sectors
+
+  dm[0] = InSecLowEdge*TMath::Tan(0.5*InnerOpenAngle)-edge;
+  dm[1] = InSecUpEdge*TMath::Tan(0.5*InnerOpenAngle)-edge;
+  dm[2] = 0.5*SecThick;
+  dm[3] = 0.5*(InSecUpEdge-InSecLowEdge);
+
+  Float_t xCenterS = InSecLowEdge+dm[3];
+
+  gMC->Gsvolu("TRCS", "TRD1", idtmed[0], dm, 4); 
+
+  //  L (Outer) sectors
+
+  dm[0] = OuSecLowEdge*TMath::Tan(0.5*OuterOpenAngle)-edge;
+  dm[1] = OuSecUpEdge*TMath::Tan(0.5*OuterOpenAngle)-edge;
+  dm[2] = 0.5*SecThick;
+  dm[3] = 0.5*(OuSecUpEdge-OuSecLowEdge);
+
+  Float_t xCenterL = OuSecLowEdge+dm[3];  
+
+  gMC->Gsvolu("TRCL", "TRD1", idtmed[0], dm, 4);
+
+  Float_t z1 = -z_side + SecThick*0.5;
+
+  //------------------------------------------------------------------
+  // S sectors - "gas sectors" (TRD1)
+  //------------------------------------------------------------------
+
+  dm[0] = InSecLowEdge*TMath::Tan(0.5*InnerOpenAngle)-0.01;
+  dm[1] = InSecUpEdge*TMath::Tan(0.5*InnerOpenAngle)-0.01;
+  dm[2] = 0.5*(250. - 0.001);
+  dm[3] = 0.5*(InSecUpEdge-InSecLowEdge);  
+
+  gMC->Gsvolu("TSGA", "TRD1", idtmed[3], dm, 4); // nonsensitive
+
+  //------------------------------------------------------------------
+  // sensitive strips - "pad rows"
+  //------------------------------------------------------------------
+
+  Int_t ns;
+  Float_t r1,r2,zz;
+
+  Float_t StripThick = 0.01; // 100 microns
+  Float_t dead = fTPCParam->GetDeadZone();
+
+  gMC->Gsvolu("TSST", "TRD1", idtmed[4], dm, 0);
+
+  dm[2] = 0.5*(250. - 0.002);
+  dm[3] = 0.5 * StripThick;
 
-  for (iss = 0; iss < fTPCParam->GetNRowLow(); ++iss) {
-    r1    = fTPCParam->GetPadRowRadiiLow(iss);
-    r2    = r1 + dm[3] * 2.;
-    dm[0] = r1 * thl - 2.63;
-    dm[1] = r2 * thl - 2.63;
 
-    zz    = -z0 + r1+dm[3];
+  // S-sector
+
+  for (ns = 0; ns < fTPCParam->GetNRowLow(); ns++) {
+
+    r1 = fTPCParam->GetPadRowRadiiLow(ns);
+    r2 = r1 + StripThick;     
+    dm[0] = r1 * TMath::Tan(0.5*InnerOpenAngle) - dead;
+    dm[1] = r2 * TMath::Tan(0.5*InnerOpenAngle) - dead;
+
+    zz = -InSecLowEdge -0.5*(InSecUpEdge-InSecLowEdge);
+    zz += r1;
+    zz += dm[3];
+
+    gMC->Gsposp("TSST", ns+1, "TSGA", 0., 0., zz, 0, "ONLY", dm, 4);
+    
 
-    pMC->Gsposp("TSST", iss+1, "TSGA", 0, 0, zz, 0, "ONLY", dm, 4);
   }
-  // ----------------------------------------------------- 
-  //  thin sensitive strips (100 microns) placed at a center 
-  //  of each pad row  in the "drift gas sector" 
-  // ----------------------------------------------------- 
-  pMC->Gsvolu("TLST", "TRD1", idtmed[403], dm, 0);
 
-  z0   = rlsl+ (rlsu - rlsl) * .5;
-  
-  for (ils = 0; ils < fTPCParam->GetNRowUp(); ++ils) {
-    r1    = fTPCParam->GetPadRowRadiiUp(ils);
-    r2    = r1 + dm[3] * 2.;
-    dm[0] = r1 * thu - 2.63;
-    dm[1] = r2 * thu - 2.63;
+  //-----------------------------------------------------------------
+  //  L sectors - "gas sectors" (PGON to avoid overlaps)
+  //-----------------------------------------------------------------
+
+  dm[0] = 360.*kDegrad - 0.5*OuterOpenAngle;
+  dm[0] *= kRaddeg;
+  dm[0] = (Float_t)TMath::Nint(dm[0]);
+
+  dm[1] = OuterOpenAngle*kRaddeg;
+  dm[1] = (Float_t)TMath::Nint(dm[1]);
+
+  dm[2] = 1.;
+  dm[3] = 4.;
+
+  dm[4] = 0.002;
+  dm[5] = OuSecLowEdge;
+  dm[6] = 252.*TMath::Cos(0.5*OuterOpenAngle)-0.002;
+
+  dm[7] = dm[4]+0.2;
+  dm[8] = dm[5];
+  dm[9] = dm[6];
+
+  dm[10] = dm[7];
+  dm[11] = OuSecLowEdge;
+  dm[12] = OuSecUpEdge;
+
+  dm[13] = 250.;
+  dm[14] = dm[11];
+  dm[15] = dm[12];
+
+  gMC->Gsvolu("TLGA","PGON",idtmed[3],dm,16);
+
+  //------------------------------------------------------------------
+  // sensitive strips - "pad rows"
+  //------------------------------------------------------------------
+
+  Float_t rmax = dm[6];
+
+  // L-sectors
+
+  gMC->Gsvolu("TLST", "PGON", idtmed[4], dm, 0);
+
+  dm[0] = 360.*kDegrad - 0.5*OuterOpenAngle;
+  dm[0] *= kRaddeg;
+  dm[0] = (Float_t)TMath::Nint(dm[0]);
+
+  dm[1] = OuterOpenAngle*kRaddeg;
+  dm[1] = (Float_t)TMath::Nint(dm[1]);
+
+  dm[2] = 1.;
+  dm[3] = 2.;
+
+  dm[7] = 250.;
+
+  Float_t xx = dead/TMath::Tan(0.5*OuterOpenAngle);
+
+  for(ns=0;ns<fTPCParam->GetNRowUp();ns++){
+
+    r1 = fTPCParam->GetPadRowRadiiUp(ns)-xx;
+    r2 = r1 + StripThick;
 
-    zz    = -z0 + r1 +dm[3];
+    dm[5] = r1;
+    dm[6] = r2;
+
+    dm[8] = r1;
+    dm[9] = r2;
+
+    if(r2+xx < rmax){
+      dm[4] = 0.002;
+    }
+    else{
+      dm[4] = 0.202;
+    }
+
+    gMC->Gsposp("TLST",ns+1,"TLGA",xx,0.,0.,0,"ONLY",dm,10);
 
-    pMC->Gsposp("TLST", ils+1, "TLGA", 0, 0, zz, 0, "ONLY", dm, 4);
   }
-  // ------------------------------------------------ 
-  //      positioning of lower sectors (1-12)*2 
-  //          rotation matrices 1-12 
-  // ------------------------------------------------ 
-  z  = (250.+0.001)/2.;
-  z1 = -z_side + sec_thick * .5;
   
-  for (il = 0; il < 12; ++il) {
-    phi1 = il * opl + 270;
-    if (phi1 > 360.) {
-      phi1 += -360;
-    }
+  //------------------------------------------------------------------
+  // Positioning of the S-sector readout chambers
+  //------------------------------------------------------------------
+
+  Float_t zs = 0.5*(250.+0.002);
+
+  Float_t theta1,theta2,theta3;
+  Float_t phi1,phi2,phi3;
+  Float_t alpha;
+  Float_t x,y;
+
+  for(ns=0;ns<nInnerSector;ns++){
+    
+    phi1 = ns * InnerOpenAngle + 270.*kDegrad + InnerAngleShift;
+    phi1 *= kRaddeg; // in degrees
+
+    phi1 = (Float_t)TMath::Nint(phi1);
+
+    if (phi1 > 360.) phi1 -= 360.;
+      
     theta1 = 90.;
     phi2   = 90.;
     theta2 = 180.;
-    phi3   = il * opl;
+    phi3   = ns * InnerOpenAngle + InnerAngleShift;
+    phi3 *= kRaddeg; // in degrees
+
+    phi3 = (Float_t)TMath::Nint(phi3);
+      
+    if(phi3 > 360.) phi3 -= 360.;
+
     theta3 = 90.;
+
+    alpha = phi3*kDegrad;
+
+    x = xCenterS * TMath::Cos(alpha);
+    y = xCenterS * TMath::Sin(alpha); 
+    AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);  
+     
+    gMC->Gspos("TRCS", ns+1, "TPSG", x, y, z1, idrotm[nRotMat], "ONLY");
+
+    gMC->Gspos("TSGA",ns+1,"TGAS",x,y,zs,idrotm[nRotMat], "ONLY");
+    gMC->Gspos("TSGA",ns+1+nInnerSector,"TGAS",x,y,-zs,idrotm[nRotMat], "ONLY");
+
+    nRotMat++;     
+
+  }
     
-    idr = il+1;
-    AliMatrix(idrotm[idr], theta1, phi1, theta2, phi2, theta3, phi3);
+  //-------------------------------------------------------------------
+  //  Positioning of the L-sectors readout chambers
+  //-------------------------------------------------------------------
     
-    alpha = il * opl * kDegrad;
-    x     = x0l * TMath::Cos(alpha);
-    y     = x0l * TMath::Sin(alpha);
+  for(ns=0;ns<nOuterSector;ns++){
+    phi1 = ns * OuterOpenAngle + 270.*kDegrad + OuterAngleShift;
+    phi1 *= kRaddeg; // in degrees
 
-    pMC->Gspos("TSGA", il+1, "TGAS", x, y, z,  idrotm[idr], "ONLY");
-    pMC->Gspos("TSGA", il+13,"TGAS", x, y, -z, idrotm[idr], "ONLY");
-    pMC->Gspos("TRCS", il+1, "TPSG", x, y, z1, idrotm[idr], "ONLY");
+    phi1 = (Float_t)TMath::Nint(phi1);
     
-  }
-  // ---------------------------------------------------- 
-  //      positioning of upper sectors (1-24)*2 
-  //          rotation matrices 13-36 
-  // ---------------------------------------------------- 
-  for (iu = 1; iu <= 24; ++iu) {
-    phi1 = (iu - 1) * opu + 270.;
-    if (phi1 > 360.) {
-      phi1 += -360.;
-    }
+
+    if (phi1 > 360.) phi1 -= 360.;
+      
     theta1 = 90.;
     phi2   = 90.;
     theta2 = 180.;
-    phi3   = (iu - 1) * opu;
+    phi3   = ns * OuterOpenAngle+OuterAngleShift;
+    phi3 *= kRaddeg; // in degrees
+
+    phi3 = (Float_t)TMath::Nint(phi3);
+
+      
+    if(phi3 > 360.) phi3 -= 360.;
+
     theta3 = 90.;
-    
-    idr = iu + 12;
-    AliMatrix(idrotm[idr], theta1, phi1, theta2, phi2, theta3, phi3);
-    
-    alpha = (iu - 1) * opu * kDegrad;
-    x     = x0u * TMath::Cos(alpha);
-    y     = x0u * TMath::Sin(alpha);
-    
-    pMC->Gspos("TLGA", iu, "TGAS", x, y, z, idrotm[idr], "ONLY");
-    pMC->Gspos("TLGA", iu+24, "TGAS", x, y, -z, idrotm[idr], "ONLY");
-    
-    pMC->Gspos("TRCL", iu, "TPSG", x, y, z1, idrotm[idr], "ONLY");
+
+    alpha = phi3*kDegrad;
+
+    x = xCenterL * TMath::Cos(alpha);
+    y = xCenterL * TMath::Sin(alpha); 
+    AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);  
+     
+
+    gMC->Gspos("TRCL", ns+1, "TPSG", x, y, z1, idrotm[nRotMat], "ONLY"); 
+
+    nRotMat++;   
+
   }
-  // -------------------------------------------------------- 
-  //             Spoke wheel structures 
-  // -------------------------------------------------------- 
-  pMC->Gsvolu("TSWS", "TUBE", idtmed[399], dm, 0);
 
-  z0 = -z_side + 2.;
-  
-  dm[0] = 82.;
-  dm[1] = 86.;
-  dm[2] = 1.;
-  
-  pMC->Gsposp("TSWS", 1, "TPSG", 0, 0, z0, 0, "ONLY", dm, 3);
-  
-  dm[0] = 253.;
-  dm[1] = 257.;
-  
-  pMC->Gsposp("TSWS", 2, "TPSG", 0, 0, z0, 0, "ONLY", dm, 3);
-  
-  dm[0] = 140.9;
-  dm[1] = 141.9;
-  
-  pMC->Gsposp("TSWS", 3, "TPSG", 0, 0, z0, 0, "ONLY", dm, 3);
-  
-  // ------------------------------------------------------- 
-  //    this volumes are to avoid overlaping 
-  // ------------------------------------------------------- 
-  z0 = 253.;
-  
-  dm[0] = 76.;
-  dm[1] = 76.+0.09776;
-  
-  pMC->Gsposp("TSWS", 4, "TPC ", 0, 0, z0, 0, "ONLY", dm, 3);
-  pMC->Gsposp("TSWS", 5, "TPC ", 0, 0, -z0, 0, "ONLY", dm, 3);
-  
-  z0 += 21.;
-  
-  pMC->Gsposp("TSWS", 6, "TPC ", 0, 0, z0, 0, "ONLY", dm, 3);
-  pMC->Gsposp("TSWS", 7, "TPC ", 0, 0, -z0, 0, "ONLY", dm, 3);
-  
-  dm[0] = 257.;
-  dm[1] = 257.+0.09776;
-  dm[2] = 11.5;
-  
-  z0 = 263.5;
+  //-------------------------------------------------------------------
+  // Positioning of the L-sectors (gas sectors)
+  //-------------------------------------------------------------------
+
+  for(ns=0;ns<nOuterSector;ns++){
+
+     phi1 = ns*OuterOpenAngle + OuterAngleShift;
+     phi1 *= kRaddeg;
+    
+     phi1 = (Float_t)TMath::Nint(phi1);
+     if(phi1>360.) phi1 -= 360.;
+
+     theta1 = 90.;
+
+     phi2 = 90. + phi1;
+     if(phi2>360.) phi2 -= 360.;
+
+     theta2 = 90.; 
+
+     phi3 = 0.;
+     theta3 = 0.;
+
+     alpha = phi1*kDegrad;
+
+
+     AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3); 
+
+
+     gMC->Gspos("TLGA",ns+1,"TGAS" ,0.,0.,0.,idrotm[nRotMat],"ONLY");
+
+     nRotMat++;
+   
+     // reflection !!
+
+     phi3 = 0.;
+     theta3 = 180.;
+     
+     AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
+  
+     gMC->Gspos("TLGA",ns+1+nOuterSector,"TGAS" ,0.,0.,0.,idrotm[nRotMat],"ONLY");
+          
+    nRotMat++;
+  }
   
-  pMC->Gsposp("TSWS", 8, "TPC ", 0, 0, z0, 0, "ONLY", dm, 3);
-  pMC->Gsposp("TSWS", 9, "TPC ", 0, 0, -z0, 0, "ONLY", dm, 3);
+  Float_t z0 = z_side - 0.95;
+
+  gMC->Gspos("TPEC",1,"TPSG",0.,0.,z0,0,"ONLY");
+
   // ========================================================== 
   //                  wheels 
   // ========================================================== 
+
+  //
+  //  auxilary structures
+  //
+
+
+  gMC->Gsvolu("TPWI","TUBE",idtmed[24],dm,0); // "air" 
+
   // ---------------------------------------------------------- 
   //       Large wheel -> positioned in the TPC 
   // ---------------------------------------------------------- 
-  dm[0] = 257.+0.09776;
+  
+
+  z0 = 263.5; // TPC length - 1/2 spoke wheel width
+
+  dm[0] = 258.;
   dm[1] = 278.;
   dm[2] = 11.5;
-  pMC->Gsvolu("TPW1", "TUBE", idtmed[399], dm, 3);
   
-  dm[0] = 259.;
+  gMC->Gsvolu("TPWL", "TUBE", idtmed[0], dm, 3); 
+
+  dm[0] = dm[0]+2.;
+  dm[1] = 278.;
+  dm[2] = dm[2]-2.;
+
+  gMC->Gsposp("TPWI",1,"TPWL",0.,0.,0.,0,"ONLY",dm,3);
+
+  gMC->Gspos("TPWL", 1, "TPC ", 0, 0, z0, 0, "ONLY");
+  gMC->Gspos("TPWL", 2, "TPC ", 0, 0, -z0, 0, "ONLY");
+
+  //
+  //  Outer vessel + CO2 HV degrader
+  //
+
+  dm[0] = 260.;
+  dm[1] = 278.;
+  dm[2] = 252.;
+
+  gMC->Gsvolu("TPCO","TUBE",idtmed[12],dm,3);
+
+  dm[0] = 275.;
   dm[1] = 278.;
-  dm[2] = 9.5;
-  
-  pMC->Gsvolu("TPW2", "TUBE", idtmed[498], dm, 3);
-    
-  pMC->Gspos("TPW2", 1, "TPW1", 0, 0, 0, 0, "ONLY");
   
-  pMC->Gspos("TPW1", 1, "TPC ", 0, 0, z0, 0, "ONLY");
-  pMC->Gspos("TPW1", 2, "TPC ", 0, 0, -z0, 0, "ONLY");
-  // ----------------------------------------------------------- 
-  //     Small wheel -> positioned in the TPSG 
-  // ----------------------------------------------------------- 
-  dm[0] = 76.+0.09776;
+  gMC->Gsvolu("TPOV","TUBE",idtmed[10],dm,3);
+
+  gMC->Gspos("TPOV",1,"TPCO",0.,0.,0.,0,"ONLY");
+
+
+  // G10 plugs
+
+  dm[0] = 258.;
+  dm[1] = 260.;
+  dm[2] = 1.;
+
+  gMC->Gsvolu("TPG1","TUBE",idtmed[8],dm,3);
+  gMC->Gspos("TPG1",1,"TPCO",0.,0.,251.,0,"ONLY");
+  gMC->Gspos("TPG1",2,"TPCO",0.,0.,-251.,0,"ONLY");  
+
+  gMC->Gspos("TPCO",1,"TPC ",0.,0.,0.,0,"ONLY");
+
+
+  //----------------------------------------------------------
+  //  Small wheel -> positioned in "side gas
+  //----------------------------------------------------------
+
+  dm[0] = 78.;
   dm[1] = 82.;
   dm[2] = 11.5;
+
+  gMC->Gsvolu("TPWS", "TUBE", idtmed[0], dm, 3);
+
+  dm[0] = 78.;
+  dm[1] = dm[1]-2;
+  dm[2] = dm[2]-2.;
+
+  gMC->Gsvolu("TPW1", "TUBE", idtmed[2], dm, 3);
   
-  pMC->Gsvolu("TPW3", "TUBE", idtmed[399], dm, 3);
-  
-  dm[0] = 76.+0.09776;
-  dm[1] = 80.;
+  gMC->Gspos("TPW1", 1, "TPWS", 0., 0., 0., 0, "ONLY");
+
+  z0 = 1.; // spoke wheel is shifted w.r.t. center of the "side gas"
+
+  gMC->Gspos("TPWS", 1, "TPSG", 0, 0, z0, 0, "ONLY");
+
+
+  // to avoid overlaps
+
+  dm[0] = 76.;
+  dm[1] = 78.;
+  dm[2] = 11.5;
+
+  gMC->Gsvolu("TPS1","TUBE",idtmed[0],dm,3);
+
   dm[2] = 9.5;
+
+  gMC->Gsvolu("TPS2","TUBE",idtmed[24],dm,3);
+
+  gMC->Gspos("TPS2",1,"TPS1",0.,0.,0.,0,"ONLY");
+
+  z0= 263.5;
   
-  pMC->Gsvolu("TPW4", "TUBE", idtmed[401], dm, 3);
-  
-  pMC->Gspos("TPW4", 1, "TPW3", 0, 0, 0, 0, "ONLY");
-  
-  z0 = 1.;
-  
-  pMC->Gspos("TPW3", 1, "TPSG", 0, 0, z0, 0, "ONLY");
-  // --------------------------------------------------------- 
-  //       spokes, inner and outer, also the inner ring 
-  // --------------------------------------------------------- 
-  
-  //Begin_Html
-  /*
-    <img src="picts/spec_tspo1.gif">
-  */
-  //End_Html
-  
-  dm[0] = 0.5*(135.9-82.1);
-  dm[1] = 3.;
+  gMC->Gspos("TPS1",1,"TPC ",0.,0.,z0,0,"ONLY");
+  gMC->Gspos("TPS1",2,"TPC ",0.,0.,-z0,0,"ONLY");
+
+  // G10 plug
+
+  dm[0] = 76.;
+  dm[2] = 78.;
+  dm[3] = 1.;
+
+  gMC->Gsvolu("TPG2","TUBE",idtmed[8],dm,3);
+
+  z0 = 251.;
+
+  gMC->Gspos("TPG2",1,"TPC ",0.,0.,z0,0,"ONLY");
+  gMC->Gspos("TPG2",2,"TPC ",0.,0.,-z0,0,"ONLY");
+
+
+  //---------------------------------------------------------
+  //  central wheel  6 (radial direction) x 4 (along z) cm2
+  //---------------------------------------------------------
+
+  dm[0] = 140.;
+  dm[1] = 146.;
   dm[2] = 2.;
-  
-  x1 = dm[0] + 82.;
-  
-  pMC->Gsvolu("TSPI", "BOX ", idtmed[399], dm, 3);
-  
-  dm[1] = 2.;
-  dm[2] = 1.;
-  
-  pMC->Gsvolu("TSP1", "BOX ", idtmed[498], dm, 3);
-  
-  pMC->Gspos("TSP1", 1, "TSPI", 0, 0, 0, 0, "ONLY");
-  
-  dm[0] = 0.5*(256.9-142.1);
+
+  gMC->Gsvolu("TPWC","TUBE",idtmed[0],dm,3);
+
+  dm[0] = dm[0] + 2.;
+  dm[1] = dm[1] - 2.;
+  dm[2] = dm[2] - 1.;
+
+  gMC->Gsposp("TPWI",2,"TPWC",0.,0.,0.,0,"ONLY",dm,3);
+
+  z0 = z_side - 1.9 - 2.;
+
+  gMC->Gspos("TPWC",1,"TPSG",0.,0.,z0,0,"ONLY");
+
+  //
+
+  gMC->Gsvolu("TPSE","BOX ",idtmed[24],dm,0); // "empty" part of the spoke 
+
+  //---------------------------------------------------------
+  //  inner spokes (nSectorInner)
+  //---------------------------------------------------------
+
+  dm[0] = 0.5*(139.9-82.1);
   dm[1] = 3.;
   dm[2] = 2.;
-  
-  x2 = dm[0] + 142.;
-  
-  pMC->Gsvolu("TSPO", "BOX ", idtmed[399], dm, 3);
-  
-  dm[1] = 2.;
-  dm[2] = 1.;
-  
-  pMC->Gsvolu("TSP2", "BOX ", idtmed[498], dm, 3);
-  
-  pMC->Gspos("TSP2", 1, "TSPO", 0, 0, 0, 0, "ONLY");
-  // -------------------------------------------------------- 
-  dm[0] = 136.;
-  dm[1] = 142.;
-  dm[2] = 2.;
-  
-  pMC->Gsvolu("TSWH", "TUBE", idtmed[399], dm, 3);
-  
-  dm[0] = 137.;
-  dm[1] = 141.;
-  dm[2] = 1.;
-  
-  pMC->Gsvolu("TSW1", "TUBE", idtmed[498], dm, 3);
-  
-  pMC->Gspos("TSW1", 1, "TSWH", 0, 0, 0, 0, "ONLY");
-  
-  z0 = z_side - .16168 - 2.;
-  // -------------------------------------------------------- 
-  pMC->Gspos("TSWH", 1, "TPSG", 0, 0, z0, 0, "ONLY");
-  // ------------------------------------------------------- 
-  //     posiioning of the inner spokes 
-  // ------------------------------------------------------- 
-  for (il = 1; il <= 6; ++il) {
-    phi1 = opl * .5 + (il - 1) * 2. * opl;
-    theta1 = 90.;
-    phi2 = opl * .5 + 90. + (il - 1) * 2. * opl;
-    if (phi2 > 360.) {
-      phi2 += -360.;
-    }
-    theta2 = 90.;
-    phi3   = 0.;
-    theta3 = 0.;
-    
+
+  Float_t x1 = dm[0]+82.;
+
+  gMC->Gsvolu("TPSI","BOX",idtmed[0],dm,3);
+
+  dm[1] = dm[1]-1.;
+  dm[2] = dm[2]-1.;
+
+  gMC->Gsposp("TPSE",1,"TPSI",0.,0.,0.,0,"ONLY",dm,3);
+
+  for(ns=0;ns<nInnerSector;ns++){
+
+    phi1 = 0.5*InnerOpenAngle + ns*InnerOpenAngle + InnerAngleShift;
+    theta1=90.;
+    phi1 *=kRaddeg;
+
+    phi1 = (Float_t)TMath::Nint(phi1);
+    if(phi1>360.) phi1 -= 360.;    
+
+    phi2 = phi1+90.;
+    if(phi2>360.) phi2 -= 360.;
+    theta2=90.;
+    phi3=0.;
+    theta3=0.;
+
     alpha = phi1 * kDegrad;
     x     = x1 * TMath::Cos(alpha);
-    y     = x1 * TMath::Sin(alpha);
-    
-    idr = il + 36;
-    
-    AliMatrix(idrotm[idr], theta1, phi1, theta2, phi2, theta3, phi3);
-    pMC->Gspos("TSPI", il, "TPSG", x, y, z0, idrotm[idr], "ONLY");
+    y     = x1 * TMath::Sin(alpha);    
+
+   AliMatrix(idrotm[nRotMat],theta1,phi1,theta2,phi2,theta3,phi3);
+
+   gMC->Gspos("TPSI",ns+1,"TPSG",x,y,z0,idrotm[nRotMat],"ONLY");  
+
+   nRotMat++;
+
   }
-  
-  for (iu = 1; iu <= 12; ++iu) {
-    phi1 = opu * .5 + (iu - 1) * 2. * opu;
-    theta1 = 90.;
-    phi2 = opu * .5 + 90. + (iu - 1) * 2. * opu;
-    if (phi2 > 360.) {
-      phi2 += -360.;
-    }
-    theta2 = 90.;
-    phi3   = 0.;
-    theta3 = 0.;
-    
+
+  //-------------------------------------------------------------
+  // outer spokes (nSectorOuter)
+  //-------------------------------------------------------------
+
+  dm[0] = 0.5*(257.9-146.1);
+  dm[1] = 3.;
+  dm[2] = 2.;
+
+  x1 = dm[0] + 146.;
+
+  gMC->Gsvolu("TPSO","BOX ",idtmed[0],dm,3);
+
+  dm[1] = dm[1] - 1.;
+  dm[2] = dm[2] - 1.;
+
+  gMC->Gsposp("TPSE",2,"TPSO",0.,0.,0.,0,"ONLY",dm,3);
+
+  for(ns=0;ns<nOuterSector;ns++){
+
+    phi1 = 0.5*OuterOpenAngle + ns*OuterOpenAngle + OuterAngleShift;
+    theta1=90.;
+    phi1 *=kRaddeg;
+
+    phi1 = (Float_t)TMath::Nint(phi1);
+    if(phi1>360.) phi1 -= 360.;
+
+    phi2 = phi1+90.;
+    if(phi2>360.) phi2 -= 360.;
+    theta2=90.;
+    phi3=0.;
+    theta3=0.;
+
     alpha = phi1 * kDegrad;
-    x     = x2 * TMath::Cos(alpha);
-    y     = x2 * TMath::Sin(alpha);
-    
-    idr = iu + 42;
-    
-    AliMatrix(idrotm[idr], theta1, phi1, theta2, phi2, theta3, phi3);
-    pMC->Gspos("TSPO", iu, "TPSG", x, y, z0, idrotm[idr], "ONLY");
-  }
-  // -------------------------------------------------------- 
-  //       endcap cover (C, 0.86% X0) 
-  // -------------------------------------------------------- 
-  dm[0] = 76.+0.09776;
-  dm[1] = 257.;
-  dm[2] = 0.16168*0.5;
-  
-  pMC->Gsvolu("TCOV", "TUBE", idtmed[407], dm, 3);
+    x     = x1 * TMath::Cos(alpha);
+    y     = x1 * TMath::Sin(alpha);    
+
+   AliMatrix(idrotm[nRotMat],theta1,phi1,theta2,phi2,theta3,phi3);
+
+   gMC->Gspos("TPSO",ns+1,"TPSG",x,y,z0,idrotm[nRotMat],"ONLY");  
+
+   nRotMat++;
+
+  }  
   
-  z0 = z_side - dm[2];
+
   
-  pMC->Gspos("TCOV", 1, "TPSG", 0, 0, z0, 0, "ONLY");
   // -------------------------------------------------------- 
   //         put the readout chambers into the TPC 
   // -------------------------------------------------------- 
+
   theta1 = 90.;
   phi1   = 0.;
   theta2 = 90.;
@@ -507,127 +700,87 @@ void AliTPCv1::CreateGeometry()
   theta3 = 180.;
   phi3   = 0.;
   
-  AliMatrix(idrotm[55], theta1, phi1, theta2, phi2, theta3, phi3);
+  AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
   
   z0 = z_side + 250.;
   
-  pMC->Gspos("TPSG", 1, "TPC ", 0, 0, z0, 0, "ONLY");
-  pMC->Gspos("TPSG", 2, "TPC ", 0, 0, -z0, idrotm[55], "ONLY");
-  // --------------------------------------------------------- 
-  //     outer gas insulation (CO2) 
-  // --------------------------------------------------------- 
-  dm[0] = 257.+0.09776;
-  dm[1] = 278.-0.25004;
-  dm[2] = 275.-23.;
-
-  pMC->Gsvolu("TPOI", "TUBE", idtmed[406], dm, 3);
-  
-  pMC->Gspos("TPHV", 1, "TGAS", 0, 0, 0, 0, "ONLY");
-  pMC->Gspos("TGAS", 1, "TPC ", 0, 0, 0, 0, "ONLY");
-  pMC->Gspos("TPOI", 1, "TPC ", 0, 0, 0, 0, "ONLY");
+  gMC->Gspos("TPSG", 1, "TPC ", 0, 0, z0, 0, "ONLY");
+  gMC->Gspos("TPSG", 2, "TPC ", 0, 0, -z0, idrotm[nRotMat], "ONLY");
   
-  pMC->Gspos("TPC ", 1, "ALIC", 0, 0, 0, 0, "ONLY");
-  // ====================================================== 
-  //      all volumes below are positioned in ALIC 
-  // ====================================================== 
-  // ------------------------------------------------------ 
-  //        the last parts of the smaller wheel (TSWS) 
-  // ------------------------------------------------------ 
-  dm[0] = 74.;
-  dm[1] = 76.;
-  dm[2] = 1.;
+  gMC->Gspos("TPC ", 1, "ALIC", 0, 0, 0, 0, "ONLY");
 
-  z0 = 253.;
-  
-  pMC->Gsposp("TSWS", 10, "TPC ", 0, 0, z0, 0, "ONLY", dm, 3);
-  pMC->Gsposp("TSWS", 11, "TPC ", 0, 0, -z0, 0, "ONLY", dm, 3);
-  
-  dm[0] = 70.;
-  
-  z0 += 21.;
-  
-  pMC->Gsposp("TSWS", 12, "TPC ", 0, 0, z0, 0, "ONLY", dm, 3);
-  pMC->Gsposp("TSWS", 13, "TPC ", 0, 0, -z0, 0, "ONLY", dm, 3);
-  // ---------------------------------------------------- 
-  //             Inner vessel (PCON) 
-  //   This volume is to be positioned directly in ALIC 
-  // ---------------------------------------------------- 
+  //----------------------------------------------------
+  //  Inner vessel and HV degrader
+  //----------------------------------------------------
 
-  //Begin_Html
-  /*
-    <img src="picts/spec_tpiv1.gif">
-  */
-  //End_Html
-  
   dm[0] = 0.;
   dm[1] = 360.;
   dm[2] = 4.;
   
   dm[3] = -250.;
-  dm[4] = 75.;
+  dm[4] = 74.4;
   dm[5] = 76.;
-  
+
   dm[6] = -64.5;
   dm[7] = 50.;
   dm[8] = 76.;
-  
-  dm[9] = 64.5;
+
+  dm[9] = -64.5;
   dm[10] = 50.;
   dm[11] = 76.;
-  
+
   dm[12] = 250.;
-  dm[13] = 75.;
+  dm[13] = 74.4;
   dm[14] = 76.;
-  
-  pMC->Gsvolu("TPIV", "PCON", idtmed[407], dm, 15);
-  // -------------------------------------------------------- 
-  //     fill the inner vessel with CO2, (HV kDegrader) 
-  //     cone parts have different thickness 
-  //     than the central barrel, according to the TP 
-  // -------------------------------------------------------- 
-  tana = 75./185.5;
+
+  gMC->Gsvolu("TPVD", "PCON", idtmed[12], dm, 15); // CO2
+
+  // cone parts
 
   dm[0] = 0.;
   dm[1] = 360.;
-  dm[2] = 6.;
-  
-  dm[3] = -(250.-0.2162);
-  dm[4] = (185.5-0.2126)*tana+0.2126;
-  dm[5] = 76-0.001;
-  
-  dm[6] = -64.5;
-  dm[7] = 50.+0.2162;
-  dm[8] = 76-0.001;
-  
-  dm[9]  = -64.5;
-  dm[10] = 50+0.05076;
-  dm[11] = 76-0.001;
-  
-  dm[12] = 64.5;
-  dm[13] = 50+0.05076;
-  dm[14] = 76-0.001;
-  
-  dm[15] = 64.5;
-  dm[16] = 50.+0.2162;
-  dm[17] = 76-0.001;
-  
-  dm[18] = (250.-0.2162);
-  dm[19] = (185.5-0.2126)*tana+0.2126;
-  dm[20] = 76-0.001;
+  dm[2] = 2.;
+
+  dm[3] = 64.5;
+  dm[4] = 50.;
+  dm[5] = 51.6;
+  dm[6] = 250.;
+  dm[7] = 74.4;
+  dm[8] = 76.;
+
+
+  gMC->Gsvolu("TIVC","PCON",idtmed[11],dm,9); // C-fibre
+
+  gMC->Gspos("TIVC",1,"TPVD",0.,0.,0.,0,"ONLY");
+  gMC->Gspos("TIVC",2,"TPVD",0.,0.,0.,idrotm[nRotMat],"ONLY");
+
+  // barrel part
+
+  dm[0] = 50.;
+  dm[1] = 50.5;
+  dm[2] = 32.25;
+
+  gMC->Gsvolu("TIVB","TUBE",idtmed[9],dm,3);
+
+  gMC->Gspos("TIVB",1,"TPVD",0.,0.,0.,0,"ONLY");
+
+  gMC->Gspos("TPVD",1,"ALIC",0.,0.,0.,0,"ONLY");
+
   
-  pMC->Gsvolu("TPVD", "PCON", idtmed[406], dm, 21);
+
   
-  pMC->Gspos("TPVD", 1, "TPIV", 0, 0, 0, 0, "ONLY");
-    
-  pMC->Gspos("TPIV", 1, "ALIC", 0, 0, 0, 0, "ONLY");
+
   // --------------------------------------------------- 
   //               volumes ordering 
   // --------------------------------------------------- 
-  pMC->Gsord("TGAS", 6);
-  pMC->Gsord("TPSG", 6);
-  pMC->Gsord("TSGA", 3);
-  pMC->Gsord("TLGA", 3);
-}
+  gMC->Gsord("TGAS", 6);
+  gMC->Gsord("TPSG", 6);
+  gMC->Gsord("TSGA", 3);
+  gMC->Gsord("TLGA", 2);
+
+} // end of function
+
 
 //_____________________________________________________________________________
 void AliTPCv1::DrawDetector()
@@ -636,49 +789,46 @@ void AliTPCv1::DrawDetector()
   // Draw a shaded view of the Time Projection Chamber version 1
   //
 
-  AliMC* pMC = AliMC::GetMC();
-
   // Set everything unseen
-  pMC->Gsatt("*", "seen", -1);
+  gMC->Gsatt("*", "seen", -1);
   // 
   // Set ALIC mother transparent
-  pMC->Gsatt("ALIC","SEEN",0);
+  gMC->Gsatt("ALIC","SEEN",0);
   //
   // Set the volumes visible
-  pMC->Gsatt("TPC","SEEN",0);
-  pMC->Gsatt("TGAS","SEEN",0);
-  pMC->Gsatt("TPSG","SEEN",0);
-  pMC->Gsatt("TPHV","SEEN",1);
-  pMC->Gsatt("TRCS","SEEN",1);
-  pMC->Gsatt("TRCL","SEEN",1);
-  pMC->Gsatt("TSST","SEEN",1);
-  pMC->Gsatt("TLST","SEEN",1);
-  pMC->Gsatt("TSWS","SEEN",1);
-  pMC->Gsatt("TPW1","SEEN",1);
-  pMC->Gsatt("TPW2","SEEN",1);
-  pMC->Gsatt("TPW3","SEEN",1);
-  pMC->Gsatt("TPW4","SEEN",1);
-  pMC->Gsatt("TSPI","SEEN",1);
-  pMC->Gsatt("TSP1","SEEN",0);
-  pMC->Gsatt("TSPO","SEEN",1);
-  pMC->Gsatt("TSP2","SEEN",0);
-  pMC->Gsatt("TSWH","SEEN",1);
-  pMC->Gsatt("TSW1","SEEN",1);
-  pMC->Gsatt("TCOV","SEEN",0);
-  pMC->Gsatt("TPOI","SEEN",1);
-  pMC->Gsatt("TPIV","SEEN",1);
-  pMC->Gsatt("TPVD","SEEN",1);
+  gMC->Gsatt("TPC","SEEN",0);
+  gMC->Gsatt("TGAS","SEEN",0);
+  gMC->Gsatt("TPSG","SEEN",0);
+  gMC->Gsatt("TPHV","SEEN",1);
+  gMC->Gsatt("TPMH","SEEN",1);
+  gMC->Gsatt("TPEC","SEEN",0);
+  gMC->Gsatt("TRCS","SEEN",1);
+  gMC->Gsatt("TRCL","SEEN",1);
+  gMC->Gsatt("TPWL","SEEN",1);
+  gMC->Gsatt("TPWI","SEEN",1);
+  gMC->Gsatt("TPWS","SEEN",1);
+  gMC->Gsatt("TPW1","SEEN",1);
+  gMC->Gsatt("TPS1","SEEN",1);
+  gMC->Gsatt("TPS2","SEEN",1);
+  gMC->Gsatt("TPG1","SEEN",1);
+  gMC->Gsatt("TPG2","SEEN",1);
+  gMC->Gsatt("TPWC","SEEN",1);
+  gMC->Gsatt("TPSI","SEEN",1); 
+  gMC->Gsatt("TPSO","SEEN",1);
+  gMC->Gsatt("TPCO","SEEN",1);
+  gMC->Gsatt("TPOV","SEEN",1);
+  gMC->Gsatt("TPVD","SEEN",1);
   //
-  pMC->Gdopt("hide", "on");
-  pMC->Gdopt("shad", "on");
-  pMC->Gsatt("*", "fill", 7);
-  pMC->SetClipBox(".");
-  pMC->SetClipBox("*", 0, 1000, -1000, 1000, -1000, 1000);
-  pMC->DefaultRange();
-  pMC->Gdraw("alic", 40, 30, 0, 12, 9.5, .025, .025);
-  pMC->Gdhead(1111, "Time Projection Chamber");
-  pMC->Gdman(18, 4, "MAN");
-  pMC->Gdopt("hide","off");
+  gMC->Gdopt("hide", "on");
+  gMC->Gdopt("shad", "on");
+  gMC->Gsatt("*", "fill", 7);
+  gMC->SetClipBox(".");
+  gMC->SetClipBox("*", 0, 1000, -1000, 1000, -1000, 1000);
+  gMC->DefaultRange();
+  gMC->Gdraw("alic", 40, 30, 0, 12, 9.5, .025, .025);
+  gMC->Gdhead(1111, "Time Projection Chamber");
+  gMC->Gdman(18, 4, "MAN");
+  gMC->Gdopt("hide","off");
 }
 
 //_____________________________________________________________________________
@@ -696,9 +846,9 @@ void AliTPCv1::Init()
   //
   // Initialises TPC detector after it has been created
   //
-  AliMC* pMC=AliMC::GetMC();
-  fIdSens1=pMC->VolId("TLST");
-  fIdSens2=pMC->VolId("TSST");
+
+  fIdSens1=gMC->VolId("TLST"); // L-sector
+  fIdSens2=gMC->VolId("TSST"); // S-sector
 
   printf("TPC version 1 initialized\n");
 }
@@ -709,26 +859,42 @@ void AliTPCv1::StepManager()
   //
   // Called at every step in the Time Projection Chamber
   //
-  Int_t         copy, id;
+  Int_t         copy, id, i;
   Float_t       hits[4];
   Int_t         vol[2];
+  TLorentzVector p;
   TClonesArray &lhits = *fHits;
-  AliMC* pMC=AliMC::GetMC();
+
+  AliTPCParam *fTPCParam = &(fDigParam->GetParam());
+  
   //
-  if(pMC->TrackCharge() && pMC->TrackEntering()) {
+
+  if(gMC->TrackCharge() && gMC->IsTrackEntering()) {
     //
     // Only entering charged tracks
-    if((id=pMC->CurrentVol(0, copy))==fIdSens1) {
-      vol[1]=copy+23;
-      id=pMC->CurrentVolOff(1,0,copy);
-      vol[0]=copy+24;
+    //
+    if((id=gMC->CurrentVolID(copy))==fIdSens1) {
+
+      // L
+
+      vol[1]=copy-1; // row
+      id=gMC->CurrentVolOffID(1,copy);
+      vol[0]=copy+fTPCParam->GetNInnerSector()-1; // sector
     } else if(id==fIdSens2) {
-      vol[1]=copy;
-      id=pMC->CurrentVolOff(1,0,copy);
-      vol[0]=copy;
+
+      // S
+
+      vol[1]=copy-1; // row
+      id=gMC->CurrentVolOffID(1,copy); // sector
+      vol[0]=copy-1;
     } else return;
-    pMC->TrackPosition(hits);
+
+    gMC->TrackPosition(p);
+    for(i=0;i<3;++i) hits[i]=p[i];
     hits[3]=0;
     new(lhits[fNhits++]) AliTPChit(fIshunt,gAlice->CurrentTrack(),vol,hits);
   }
 }
+
+
+