Flexible ring radii, a new Boolean switch for module A, module coverage in eta independent of their position

Author: pkurash

Detectors/Upgrades/ALICE3/FD/base/include/FDBase/Constants.h

@@ -25,6 +25,12 @@ struct Constants {
   static constexpr int nsect = 8;
   static constexpr int nringsA = 5;
   static constexpr int nringsC = 6;
+
+  static constexpr float etaMax = 7.0f;
+  static constexpr float etaMin = 4.0f;
+
+  static constexpr int nringsA_withFCT = 4;
+  static constexpr float etaMinA_withFCT = 5.0f;
 };
 
 } // namespace fd

Detectors/Upgrades/ALICE3/FD/base/include/FDBase/FDBaseParam.h

@@ -22,12 +22,11 @@ namespace fd
 {
 struct FDBaseParam : public o2::conf::ConfigurableParamHelper<FDBaseParam> {
 
-  float ringsA[Constants::nringsA + 1] = {3., 14.8, 26.6, 38.4, 50.2, 62.};
-  float ringsC[Constants::nringsC + 1] = {3.5, 14.75, 26.0, 37.25, 48.5, 59.75, 71.};
+  float zmodA = 1700.0f;
+  float zmodC = -1950.0f;
+  float dzscint = 4.0f;
 
-  float zmodA = 1700;
-  float zmodC = -1950;
-  float dzscint = 4.;
+  bool withFCT = true;
 
   O2ParamDef(FDBaseParam, "FDBase");
 };

Detectors/Upgrades/ALICE3/FD/simulation/include/FDSimulation/Detector.h

@@ -98,6 +98,8 @@ class Detector : public o2::base::DetImpl<Detector>
   TGeoVolumeAssembly* buildModuleA();
   TGeoVolumeAssembly* buildModuleC();
 
+  float ringRadius(float zmod, float eta);
+
   int mNumberOfSectors;
   int mNumberOfRingsA;
   int mNumberOfRingsC;
@@ -106,6 +108,7 @@ class Detector : public o2::base::DetImpl<Detector>
   std::vector<float> mRingRadiiA = {};
   std::vector<float> mRingRadiiC = {};
 
+  float mEtaMax, mEtaMin, mEtaMinA;
   float mZmodA;
   float mZmodC;
 

Detectors/Upgrades/ALICE3/FD/simulation/src/Detector.cxx

@@ -55,23 +55,37 @@ Detector::Detector(bool active)
     mGeometryTGeo(nullptr),
     mTrackData()
 {
-  mNumberOfRingsA = Constants::nringsA;
   mNumberOfRingsC = Constants::nringsC;
   mNumberOfSectors = Constants::nsect;
 
+  mEtaMax = Constants::etaMax;
+  mEtaMin = Constants::etaMin;
+
   auto& baseParam = FDBaseParam::Instance();
 
+  if (baseParam.withFCT) {
+    mNumberOfRingsA = Constants::nringsA_withFCT;
+    mEtaMinA = Constants::etaMinA_withFCT;
+  } else {
+    mNumberOfRingsA = Constants::nringsA;
+    mEtaMinA = mEtaMin;
+  }
+
   mDzScint = baseParam.dzscint / 2;
+  mZmodA = baseParam.zmodA;
+  mZmodC = baseParam.zmodC;
 
   for (int i = 0; i <= mNumberOfRingsA + 1; i++) {
-    mRingRadiiA.emplace_back(baseParam.ringsA[i]);
+    float eta = mEtaMax - i * (mEtaMax - mEtaMinA) / mNumberOfRingsA;
+    float r = ringRadius(mZmodA, eta);
+    mRingRadiiA.emplace_back(r);
   }
+
   for (int i = 0; i <= mNumberOfRingsC + 1; i++) {
-    mRingRadiiC.emplace_back(baseParam.ringsC[i]);
+    float eta = -mEtaMax + i * (mEtaMax - mEtaMin) / mNumberOfRingsC;
+    float r = ringRadius(mZmodC, eta);
+    mRingRadiiC.emplace_back(r);
   }
-
-  mZmodA = baseParam.zmodA;
-  mZmodC = baseParam.zmodC;
 }
 
 Detector::Detector(const Detector& rhs)
@@ -297,11 +311,12 @@ TGeoVolumeAssembly* Detector::buildModuleA()
   for (int ir = 0; ir < mNumberOfRingsA; ir++) {
     std::string rName = "fd_ring" + std::to_string(ir + 1);
     TGeoVolumeAssembly* ring = new TGeoVolumeAssembly(rName.c_str());
+    float rmin = mRingRadiiA[ir];
+    float rmax = mRingRadiiA[ir + 1];
+    LOG(info) << "ring" << ir << ": from " << rmin << " to " << rmax;
     for (int ic = 0; ic < mNumberOfSectors; ic++) {
       int cellId = ic + mNumberOfSectors * ir;
       std::string nodeName = "fd_node" + std::to_string(cellId);
-      float rmin = mRingRadiiA[ir];
-      float rmax = mRingRadiiA[ir + 1];
       float phimin = dphiDeg * ic;
       float phimax = dphiDeg * (ic + 1);
       auto tbs = new TGeoTubeSeg("tbs", rmin, rmax, mDzScint, phimin, phimax);
@@ -326,11 +341,12 @@ TGeoVolumeAssembly* Detector::buildModuleC()
   for (int ir = 0; ir < mNumberOfRingsC; ir++) {
     std::string rName = "fd_ring" + std::to_string(ir + 1 + mNumberOfRingsA);
     TGeoVolumeAssembly* ring = new TGeoVolumeAssembly(rName.c_str());
+    float rmin = mRingRadiiC[ir];
+    float rmax = mRingRadiiC[ir + 1];
+    LOG(info) << "ring" << ir + mNumberOfRingsA << ": from " << rmin << " to " << rmax;
     for (int ic = 0; ic < mNumberOfSectors; ic++) {
       int cellId = ic + mNumberOfSectors * (ir + mNumberOfRingsA);
       std::string nodeName = "fd_node" + std::to_string(cellId);
-      float rmin = mRingRadiiC[ir];
-      float rmax = mRingRadiiC[ir + 1];
       float phimin = dphiDeg * ic;
       float phimax = dphiDeg * (ic + 1);
       auto tbs = new TGeoTubeSeg("tbs", rmin, rmax, mDzScint, phimin, phimax);
@@ -354,6 +370,8 @@ void Detector::defineSensitiveVolumes()
   int nCellA = mNumberOfRingsA * mNumberOfSectors;
   int nCellC = mNumberOfRingsC * mNumberOfSectors;
 
+  LOG(info) << "number of A rings = " << mNumberOfRingsA << " number of cells = " << nCellA;
+
   for (int iv = 0; iv < nCellA + nCellC; iv++) {
     volumeName = "fd_node" + std::to_string(iv);
     v = gGeoManager->GetVolume(volumeName);
@@ -390,4 +408,9 @@ int Detector::getChannelId(TVector3 vec)
   return ir * mNumberOfSectors + isect + noff;
 }
 
+float Detector::ringRadius(float z, float eta)
+{
+  return z * TMath::Tan(2 * TMath::ATan(TMath::Exp(-eta)));
+}
+
 ClassImp(o2::fd::Detector);